JP3838344B2 - Cylinder bore surface processing method and perforated sidewall surface processing method - Google Patents

Description

【００６８】
なお表１中で高圧水の種類とは、本実施例において高圧水噴射ノズルから噴射する高圧水の種類である。圧力とは高圧水ポンプの圧力を意味し、水量とは高圧水噴射ノズルから噴射される高圧水の水量をいう。またブラスト材はショットブラストに用いる粒子を意味し、本試験においてはアルミナ粒子を用いた。アルミナ粒子としては、アルミナ＃２４を用いた。なおシリンダボア面に溶射する溶射材は、全てＦｅ−１％Ｃの鉄基材料を用いた
試験例１では、有機溶媒の洗浄液に浸すディッピングでシリンダボア面を洗浄することを３回繰り返して洗浄した。その後アルミナ粒子によるショットブラストによってシリンダボア面の粗面化を行う。そしてエアークリーニングの方法でシリンダボア面を乾燥させてからＦe−１％Ｃの鉄基材料をシリンダボア面に溶射して皮膜を形成した。
【００６９】
試験例２では、洗浄を行わず、アルミナ粒子によるショットブラストによってシリンダボア面の粗面化を行う。そしてエアークリーニングの方法でシリンダボア面を乾燥させてからＦe−１％Ｃの鉄基材料をシリンダボア面に溶射して皮膜を形成した。
【００７０】
試験例３〜試験例７では、本実施例を実施してシリンダボア面を処理した。即ち本発明のシリンダボア面の処理方法を実施した。そしてシリンダボア面をエアー乾燥した。その後乾燥したシリンダボア面にＦｅ−１％Ｃの鉄基材料をシリンダボア面に溶射して皮膜を形成した。なお試験例３〜試験例５は高圧水として水道水を用い、試験例６と試験例７は高圧水として炭酸ソーダ水を用いた。なお圧力、水量は表１に記載の通りである。
【００７１】
試験例８と試験例９は、本実施例を実施してシリンダボア面を処理し、シリンダボア面をエアー乾燥した後に、アルミナ粒子によるショットブラストによってシリンダボア面の粗面化を更に行った。そしてエアークリーニングの方法でシリンダボア面を乾燥させてからシリンダボア面にＦｅ−１％Ｃの鉄基材料を溶射してシリンダボア面に皮膜を形成そた・
なお試験例１〜試験例９のいずれの例も皮膜が形成されたシリンダボア面を冷却して、ホーニング加工等の後加工を行った。
【００７２】
皮膜密着強度試験の結果を図６に示す。なお皮膜の密着強度は剪断法にて測定した。図６においては、棒グラフは密着強度の平均値を示し、矢印は密着強度のばらつきを示す。
【００７３】
試験例１は、試験例３〜９の本発明の実施例を用いた場合と比較すると概ね同程度の密着強度の平均値を有しているが、密着強度のばらつきが著しく大きいことが分かる。このように試験例１において、皮膜の密着強度のばらつきが大きいのは鋳巣に残留したクーランド等の作業油を洗浄において除去することができず、シリンダボア面における作業油の油分が完全に洗浄された領域とショットブラストによって鋳巣から作業油が飛び出したり溶射によって作業油が滲み出て油分に汚染された領域との相違によると考えられる。
【００７４】
試験例２のように洗浄せずにショットブラストのみをシリンダボア面に施した場合には、皮膜の密着強度の平均値自体が低く、また密着強度のばらつきも大きかった。
【００７５】
なおここで試験例２のシリンダボア面に現れた鋳巣の外観写真を図７、図８、図９に示す。図７の鋳巣は概ねφ０．６５ｍｍの鋳巣である。図８の鋳巣は概ね１．１×０．４ｍｍの鋳巣である。そして図９の鋳巣は１．８×０．６ｍｍの鋳巣である。
【００７６】
更に試験例１のシリンダボア面の鋳巣が顕著に多かった領域の鋳巣付近での皮膜の密着強度と全く鋳巣が見られなかった領域での皮膜の密着強度を測定した。ここでも剪断法によって測定した。図１０にその測定結果を示す。
【００７７】
鋳巣の付近の皮膜の密着強度は、鋳巣が無い領域の皮膜の密着強度よりも著しく低いことが分かる。このように試験例１において鋳巣付近の領域と鋳巣がない領域とでは皮膜の密着強度が大きく異なるのは、鋳巣付近の領域は油分に汚染されているからと考えられる。
【００７８】
試験例３から試験例９は本実施例のシリンダボア面の処理方法を用いた例である。なお試験例８及び試験例９は、本実施例のシリンダボア面の処理方法を行った後にショットブラストを行った例である。
【００７９】
試験例３は、密着強度のばらつきが試験例１よりも少ないが、試験例４〜試験例９よりは大きくなっている。試験例１よりはばらつきが少なくなっているのは、試験例１よりは均等に油分を除去できているからと考えられる。また試験例４〜試験例９よりはばらつきが大きくなっているのは、高圧水ポンプの圧力が低く、高圧水の水量が少ないからと考えられる。即ち先の被削量の測定試験によれば、２０５ＭＰａ、３．０７Ｌ／分のときは０．０２ｍｍであるので、鋳巣中の油分が十分に除去されなかったからと考えられる。
【００８０】
試験例４から試験例９は、密着強度の平均値は試験例１と概ね同程度であるが、密着強度のばらつきは試験例１よりは大幅に小さくなっている。これは試験例４から試験例９については、表面の被削量が大きくなることによって、試験例１と比較すると確実に鋳巣の内部に残留した油分を除去できているからだと考えられる。
【００８１】
詳しく述べると試験例３から試験例５は、高圧水ポンプの圧力及び高圧水の水量が異なるのみで後は同じ条件である。なお高圧水の種類は水道水である。圧力及び水量が大きくなるにしたがって、密着強度の平均値が大きくなり、密着強度のばらつきが小さくなっていることが分かる。これは被削量が大きくなることによって、表面の粗さが大きくなり密着強度が向上し、また鋳巣に残留した油分をより多く除去しているからと考えられる。
【００８２】
なお表１で示す条件で行った試験以外に、高圧水の種類を水道水、圧力を３８０ＭＰａ、水量を高圧水噴射ノズル１個当たり４．１６Ｌ／分という条件で表面を０．２１ｍｍまで被削した場合についても密着強度を確認したが、試験例５の場合と大きく変化しなかった。
【００８３】
なお試験例６と試験例７は、高圧水としてアルカリ洗浄において用いられる炭酸ソーダ水を用いた例である。試験例６は高圧水の種類が異なるのみで、後の条件は試験例４と同じである。同様に試験例７も高圧水の種類が異なるのみで、後の条件は試験例５と同じである。試験例４と試験例６を比較すると、密着強度の平均値は試験例６の方が若干向上しており、密着強度のばらつきも試験例６の方が向上している。試験例５と試験例７を比較すると、密着強度の平均は試験例５の方が若干よく、密着強度のばらつきも若干試験例５の方が小さかった。いずれにせよ水道水を用いても炭酸ソーダ水を用いてもそれほどの違いは出ないことが分かる。
【００８４】
試験例８と試験例９は、試験例４と試験例５の後にショットブラストを行った例である。密着強度の平均値及び密着強度のばらつきについてそれぞれ若干向上していることが分かる。
【００８５】
なおこの試験はシリンダボア面について行った試験であるが、特にシリンダボア面というように形成されていなくても、円柱状に形成された穿孔の側壁面であれば同等の結果を得ることができる。
【００８６】
（鋳巣の観察試験）
本観察試験では、本発明のシリンダボア面の処理方法を用いてシリンダボア面を処理して、溶射皮膜を形成したときの鋳巣の断面を観察した。なおシリンダボア面を構成する材料はＡＤＣ１２を用いた。
【００８７】
本観察試験では、シリンダボア面に開口した鋳巣として内径がφ０．８ｍｍの人工鋳巣を設けた。またシリンダボア面の処理方法の設定条件は、高圧水噴射ノズルの内径をφ０．３８１ｍｍとし、高圧水噴射ノズルからの水量を３．０７Ｌ／分と４．１６Ｌ／分と２種類設定した。またこのときの高圧水ポンプの圧力は３８０ＭＰａとした。また高圧水噴射ノズルの軸方向への移動速度は、水量が３．０７Ｌ／分の方を２ｍｍ／秒とし、水量が４．１６Ｌ／分の方を４ｍｍ／秒として設定した。更に高圧水噴射ノズルの回転数はいずれも６５０ｒｐｍとした。高圧水噴射ノズルをシリンダボア面の全長を軸方向に１回移動させた。なおシリンダボアの軸方向の長さは１３５ｍｍであり、シリンダボアの内径はφ８２ｍｍであった。
【００８８】
更に上記条件でシリンダボア面の表面を処理した後、溶射によって鉄基系の皮膜を形成した。厚さが０．１ｍｍとなるように皮膜を形成した。
【００８９】
このように皮膜を形成したときの人工鋳巣の断面の写真を図１１及び図１２に示す。図１１は、水量が３．０７Ｌ／分で移動速度が２ｍｍ／秒で処理した場合の断面の写真であり、図１２は水量が４．１６Ｌ／分で移動速度が４ｍｍ／秒で処理した場合の断面の写真である。
【００９０】
図１１及び図１２から本発明のシリンダボア面の処理方法を実施することにより、人工鋳巣の開口部が押しつぶされて小さくなっていることが分かる。これは高圧の流体で効率よく、シリンダボア面をエロージョン除去してシリンダボア面の表面を微小に切削して洗浄すると同時に、大量の流体を一定の移動速度で人工鋳巣の上を移動させることによって人工鋳巣の開口部のエッジ部分を塑性流動させるからである。
【００９１】
低炭素鉄合金を溶射して０．１〜０．２ｍｍの膜厚の皮膜を形成する場合には内径がφ０．５ｍｍ以下の鋳巣については溶射による皮膜で埋めることが可能であることが見出されている。従って内径がφ０．５〜０．８ｍｍの鋳巣についての対策が課題とされていた。
【００９２】
本発明のシリンダボア面の処理方法においては、水量を３．０７Ｌ／分で移動速度が２ｍｍ／秒に設定したときも、水量を４．１６Ｌ／分で移動速度を４ｍｍ／秒で設定した場合も鋳巣の開口部のエッジ部分を塑性流動させて開口部を閉口しながら洗浄していることが分かる。
【００９３】
なお参考までに特許２５８６９８６号の請求項２及び請求項５に記載された条件の範囲内のシリンダボア面を処理した場合の人工鋳巣の断面の写真を図１３に示す。シリンダボア面の処理条件を更に具体的に述べると、高圧水噴射ノズルの内径をφ０．１５ｍｍ、水量を０．５７Ｌ／分、高圧水噴射ノズルの軸方向の移動速度を２ｍｍ／秒、高圧水噴射ノズルの回転数を６５０ｒｐｍとした。なおここではシリンダボア面に設けられた人工鋳巣の内径はφ０．６ｍｍとし、溶射による皮膜は膜厚が０．３ｍｍとなるように形成した。この条件でシリンダボア面を処理した場合には開口部には変化が生じていないことが分かる。
【００９４】
（開口部縮小率の測定試験）
本測定試験では、シリンダボア面に開口した鋳巣として内径がφ０．８ｍｍの人工鋳巣を設けて、このシリンダボア面に高圧水を噴射して開口部がどの程度縮小するか即ちどの程度閉口するかを測定した。なおシリンダボア面を構成する材料はＡＤＣ１２を用いた。
【００９５】
シリンダボア面の処理方法の設定条件は、高圧水噴射ノズルの内径をφ０．３８１ｍｍとし、高圧水噴射ノズルの回転数はいずれも６５０ｒｐｍとした。高圧水噴射ノズルからの高圧水の水量及び高圧水噴射ノズルの移動速度は、複数設定した。即ち高圧水噴射ノズルの移動速度は、１ｍｍ／秒、１．５ｍｍ／秒、２ｍｍ／秒、４ｍｍ／秒の４種類設定した。また一つの高圧水噴射ノズルからの水量は、２．１７Ｌ／分、２．５１Ｌ／分、３．０７Ｌ／分、３．５５Ｌ／分、４．３５Ｌ／分と設定した。高圧水噴射ノズルをシリンダボアの全長を軸方向に１回移動させた。
【００９６】
なおシリンダボアの軸方向の長さは１３５ｍｍであり、シリンダボアの内径はφ８２ｍｍであった。
【００９７】
これらの結果を図１４に示す。これらの結果から水量が３．０７Ｌ／分を超えた場合であって、高圧水噴射ノズルの移動速度が１ｍｍ／秒、１．５ｍｍ／秒、２ｍｍ／秒のときに、内径がφ０．８ｍｍの開口部が閉口して径が０．５ｍｍ以下となることが分かる。従って高圧水噴射ノズルの軸方向の移動速度は１〜３ｍｍ／秒程度に設定することが好ましいと考えられる。
【００９８】
（被照射領域の観察試験）
次に高圧水噴射ノズルの内径と高圧水が被照射される領域即ち被照射領域との関係について観察した。
【００９９】
図１５及び図１６に特許２５８６９８６号の請求項２及び請求項５に記載された条件の範囲内で高圧水を噴射した場合のシリンダボア面の写真を示す。図１６は図１５の一部を拡大した写真である。また本発明のシリンダボア面の処理方法を実施して処理した場合のシリンダボア面の写真を図１７に示す。
【０１００】
ここで特許２５８６９８６号の請求項２及び請求項５に記載された条件の範囲内で高圧水を噴射する場合の具体的な条件を述べると、高圧水噴射ノズルの内径はφ０．１５ｍｍ、高圧水ポンプの圧力は２７６ＭＰａ、水量は０．５７Ｌ／分、高圧水噴射ノズルの軸方向の移動速度は２ｍｍ／秒、高圧水噴射ノズルの回転数は６５０ｒｐｍである。なお以下の記載で特許２５８６９８６号の条件とは、ここで述べた条件を言う。
【０１０１】
なお特許２５８６９８６号の請求項２には圧力として「２５．０００ｐｓｉと６０．０００ｐｓｉの間に」と記載され、請求項５には高圧水噴射ノズルの内径として「０．００５インチから０．００６インチ」と記載されている。
【０１０２】
これに対して本発明の具体的な条件を述べると、高圧水噴射ノズルの内径はφ０．３８ｍｍ、高圧水ポンプの圧力は３１０ＭＰａ、水量は３．７６Ｌ／分、高圧水噴射ノズルの軸方向の移動速度は１．５ｍｍ／秒、高圧水噴射ノズルの回転数は６５０ｒｐｍである。なお以下の記載で本発明の条件とはここで述べた条件を言う。
【０１０３】
なおいずれの場合も、なおシリンダボアの軸方向の長さは１３５ｍｍであり、シリンダボアの内径はφ８２ｍｍであった。また高圧水噴射ノズルをシリンダボアの全長を軸方向に１回移動させた。
【０１０４】
特許２５８６９８６号の条件で高圧水を噴射した場合には、図１５及び図１６からシリンダボア面がストライプ状に処理されたが分かる。即ち処理のあり方にむらができると言うことが分かる。これに対して、本発明の条件でシリンダボア面を処理した場合にはむらが生じていないことが分かる。
【０１０５】
これは特許２５６６９８６号の条件で処理する場合には、高圧水噴射ノズルの内径が小さいために高圧水の衝撃エネルギーが集中する被照射領域の面積が狭くなっているからと考えられる。これに対して本発明の条件で処理した場合には高圧水噴射ノズルの内径が大きくなっているために高圧水の衝撃エネルギーが集中する被照射領域の面積が適度な広さになっていると考えられる。
【０１０６】
ここで高圧水の噴射の様子、照射パターン、エネルギーパターンを図１８に示す。図１８（Ａ）は特許２５８６９８６号の条件で処理する場合を示し、図１８（Ｂ）は本発明の条件で処理する場合を示す。
【０１０７】
このように特許２５８６９８６号の条件で処理する場合においては、高圧水噴射ノズルを回転させながら軸方向に移動させることから、例えば硬度がブリネル５０〜１００のダクタイル金属では高圧水噴射ノズルの中心の被照射領域（以下適宜「中心被照射領域」という）とこの被照射領域に軸方向に隣接する高圧水噴射ノズルの中心被照射領域との間に間隙の領域（以下適宜「間隙領域」という）が生じることになる。そしてこの間隙領域と中心被照射領域とでは被削の程度が大きくなる。その結果シリンダボア面に被削の程度が大きい中心被照射領域と被削の程度が小さい間隙領域とがストライプ状に生ずることになる。
【０１０８】
これに対して本発明の条件でシリンダボア面を処理する場合には中心被照射領域が適度な面積を有するので、高圧水噴射ノズルの中心被照射領域とこの中心被照射領域に軸方向に隣接する中心被照射領域との間に間隙が生じるということはない。
【０１０９】
ここで図１９（Ａ）は特許２５８６９８６号の条件で処理した場合のシリンダボア面の被削の状態を示し、図１９（Ｂ）は本発明の条件で処理した場合のシリンダボア面の被削の状態を示す。図１９（Ａ）が示すように、特許２５８６９８６号の条件で処理した場合には、中心被照射領域と隣接する中心被照射領域との間に間隙が生じて、大きなうねりが形成される。これに対して図１９（Ｂ）に示すように本発明の条件で処理した場合にはうねりは存在しない。
【０１１０】
ここで処理されたシリンダボア面の表面の粗さのグラフを図２０に示す。図２０（Ａ）は特許２５８６９８６号の条件で処理した場合のシリンダボア面の表面の粗さを示し、図２０（Ｂ）は本発明の条件で処理した場合のシリンダボア面の表面の粗さを示す。
【０１１１】
図２０（Ａ）において示すように、特許２５８６９８６号の条件で処理した場合にはシリンダボア面に山部と谷部が形成された。図２０においては中心被照射領域を▲１▼で示し、間隙領域を▲２▼で示した。衝撃エネルギーが集中する中心被照射領域が谷部となり、間隙領域が山部を構成した。特許２５８６９８６号で処理した場合にはシリンダボア面の表面粗さは全体としては旧ＪＩＳで概ね４０〜６０Ｒｚの数値を得ることができたが、間隙領域である山部については概ね５〜２０Ｒｚ程度の数値しか得ることができなかった。なお経験上溶射した皮膜に必要な密着強度を得ることができる表面粗さは概ね旧ＪＩＳの表面粗さで１３Ｒｚであることが確認されており、この数値では溶射した皮膜に必要な密着強度を得ることはできない。
【０１１２】
本発明の条件で処理した場合においては、図２０（Ｂ）で示すように、中心被照射領域と間隙領域との区別がない。従って山部、谷部を構成することはなく、中心被照射領域と間隙領域の部分的な表面粗さとシリンダボア面全体の表面粗さの間に差が生じることはなかった。これはシリンダボア面全体について表面を均一に被削したからと考えられる。
【０１１３】
なお特許２５８６９８６号の条件で処理した場合のように、シリンダボア面に山部と谷部とが生じてその深さに差が生じると、溶射後の後加工ではシリンダボア面の表面を平滑にする必要があるために必然的に深い谷部に合わせて溶射皮膜の厚さを決定しなければならない。このことはサイクルタイムの増加に加えて、皮膜の厚さの増大に伴う皮膜内の引っ張り残留応力も増大し、皮膜の密着強度に悪影響を与えることになる。
【０１１４】
更に山部と谷部が存在するとその山部によって谷部への溶射に対して悪影響を与える場合がある。これは溶射施工でよく言われる遮断効果が現れるということである。ここで遮断効果が現れたシリンダボア面を示す写真を図２１に示す。図２１に示すシリンダボア面は図１５で示したシリンダボア面に対して溶射を行ったものである。このように遮断効果の典型的な空孔が観察される。これは皮膜の品質にとって好ましいものではない。
【０１１５】
本発明の条件で処理した場合においては、山部と谷部との区別が発生しないので上述の欠点を免れることができる。
【０１１６】
なお以上述べたことは、シリンダボア面に限らず、円柱状に形成された穿孔の側壁面についても同様に述べることができる。
【０１１７】
【発明の効果】
皮膜の形成するための前処理として、本発明のシリンダボア面の処理方法及び本発明の穿孔側壁面の処理方法を用いて皮膜シリンダボア面、穿孔の側壁面を処理することによって、皮膜の密着強度を向上させることができる。
【図面の簡単な説明】
【図１】 被削量の測定試験及び皮膜の密着強度試験において用いた高圧水噴射装置の概略を模式的に示した図である。
【図２】 被削量の測定試験及び皮膜の密着強度試験において用いた高圧水噴射装置のノズルボディの概略を示した図である。
【図３】 高圧水ポンプの圧力とシリンダボア面の被削量との関係を示すグラフである。
【図４】 圧力を２７６ＭＰａで水量を３．５５Ｌ／分としてシリンダボア面の表面を０．０７５ｍｍ被削したときのシリンダボア面を拡大した写真である。
【図５】 図４を更に拡大した図である。
【図６】 皮膜密着強度試験の結果を示す図である。
【図７】 シリンダボア面に現れた鋳巣の外観を示す写真である。
【図８】 シリンダボア面に現れた鋳巣の外観を示す写真である。
【図９】 シリンダボア面に現れた鋳巣の外観を示す写真である。
【図１０】 シリンダボア面の鋳巣が顕著に多かった領域の鋳巣付近での皮膜の密着強度と全く鋳巣が見られなかった領域での皮膜の密着強度を測定した結果を示す図である。
【図１１】 皮膜を形成したときの人工鋳巣の断面の写真であって、水量が３．０７Ｌ／分で移動速度が２ｍｍ／秒で処理した場合の断面の写真である。
【図１２】 皮膜を形成したときの人工鋳巣の断面の写真であって、水量が４．１６Ｌ／分で移動速度が４ｍｍ／秒で処理した場合の断面の写真である。
【図１３】 皮膜を形成したときの人工鋳巣の断面写真であって、特許２５８６９８６号の請求項２及び請求項５に記載された条件の範囲内のシリンダボア面を処理した場合の人工鋳巣の断面の写真である。
【図１４】 開口部縮小率測定試験の結果を示す図である。
【図１５】 特許２５８６９８６号の請求項２及び請求項５に記載された条件の範囲内で高圧水を噴射した場合のシリンダボア面の写真である。
【図１６】 特許２５８６９８６号の請求項２及び請求項５に記載された条件の範囲内で高圧水を噴射した場合のシリンダボア面の写真である。
【図１７】 本発明のシリンダボア面の処理方法を実施して処理した場合のシリンダボア面の写真である。
【図１８】 高圧水の噴射の様子、照射パターン、エネルギーパターンを示す図である。図１８（Ａ）は特許２５８６９８６号の条件で処理する場合を示し、図１８（Ｂ）は本発明の条件で処理する場合を示す。
【図１９】 シリンダボア面の被削の状態を示した図である。図１９（Ａ）は特許２５８６９８６号の条件で処理した場合のシリンダボア面の被削の状態を示し、図１９（Ｂ）は本発明の条件で処理した場合のシリンダボア面の被削の状態を示す
【図２０】 処理されたシリンダボア面の表面の粗さのグラフを示す図である。図２０（Ａ）は特許２５８６９８６号の条件で処理した場合のシリンダボア面の表面の粗さを示し、図２０（Ｂ）は本発明の条件で処理した場合のシリンダボア面の表面の粗さを示す。
【図２１】 遮断効果が現れたシリンダボア面を示す写真である。
【図２２】 本発明のシリンダボアの処理方法を用いて皮膜を形成する場合の工程を示す図である。
【図２３】 従来行われているシリンダボア面に溶射によって皮膜を形成する工程を示す。
【図２４】 従来の工程においてクーランドが鋳巣内部に残留して、ショットブラスト後にクーランドが飛び出す様子を示した図である。
【符号の説明】
Ｘ：鋳巣
Ｙ：シリンダボア面
Ｚ：クーランド
１０：高圧水噴射ポンプ
２０：高圧水配管
３０：マニプレータ
４０：ノズルボディ
５０：高圧水噴射ノズル
１００：高圧水噴射装置
１１０：シリンダブロック
１２０：シリンダボア
１３０：シリンダボア面[0001]
[Prior art]
The present invention relates to a cylinder bore surface processing method and a perforated side wall surface processing method. More specifically, the present invention relates to a surface treatment method before forming a film on the surfaces of a cylinder bore surface and a perforated side wall surface, and relates to a treatment method using a high-pressure water injection device.
[0002]
[Prior art]
In recent years, aluminum alloys have been used for cylinder blocks of engines such as automobiles, motorcycles and airplanes from the viewpoint of weight reduction. In this case, the bore surface of the aluminum alloy cylinder block has been cast or pressed into with a cast iron cylinder liner from the viewpoint of wear resistance, heat resistance and the like. However, from the viewpoint of further promoting weight reduction, instead of cast iron cylinder liners, the bore surface is cast with an aluminum alloy cylinder liner, or an iron-based material containing carbon or the like with a thickness of 0.2 mm or less. Techniques for thermal spraying have been studied.
[0003]
[Problems to be solved by the invention]
However, the cylinder liner made of an aluminum alloy does not sufficiently solve the problem of high temperature deformation for a high cost. Further, the thermal spraying method in which a coating is formed on the cylinder bore surface by spraying an iron-based material or the like has been questioned in reliability represented by the adhesion of the coating formed by thermal spraying, and has been demanded to be improved.
[0004]
The inventors of the present invention have repeatedly studied why the reliability of the adhesion of the film formed by thermal spraying remains unclear, and have obtained the following knowledge.
[0005]
Here, FIG. 23 shows a conventional process for forming a film on the cylinder bore surface by thermal spraying. In the conventional process, first, cleaning the cylinder bore surface by so-called dipping soaked in a cleaning liquid such as an organic solvent or an alkaline degreasing agent is repeated a plurality of times as a treatment before spraying to form a film on the cylinder bore surface. Thereafter, the cylinder bore surface is roughened by shot blasting. Then, the cylinder bore surface is dried by air cleaning. Thermal spraying is performed on the dried cylinder bore surface to form a coating on the cylinder bore surface. Thereafter, the cylinder bore surface on which the film is formed is cooled, and thereafter, honing is performed, or post-processing such as honing is performed after boring is performed again.
[0006]
In this case, the cylinder block in which the cylinder bore is formed is usually manufactured by casting. However, products produced by current casting, such as die casting, cannot avoid the occurrence of casting defects, that is, casting voids. For example, by performing so-called defect-free casting such as vacuum casting, it is possible to largely prevent the occurrence of a conventional cast hole of several millimeters. However, it has been found that it is impossible to prevent the occurrence of a relatively small casting hole having a diameter of about 0.01 to 0.8 mm. Therefore, the cylinder block manufactured by die casting also has a cast hole.
[0007]
Then, when the cylinder bore is formed by boring the cylinder block formed by casting, as shown in FIGS. 24A and 24B, the casting hole X is opened on the cylinder bore surface Y formed by the boring, The working oil such as Cooland Z used for boring enters the inside of the opened casting hole X.
[0008]
In this case, in the cleaning by the dipping method in the process of forming the conventional film, as shown in FIG. 24C, if the opening of the casting hole X opened in the cylinder bore surface Y is narrow and the inside of the casting hole X is wide, the casting hole The working oil such as Cooland Z accumulated in X cannot be sufficiently removed and remains in the casting cavity.
[0009]
Then, as shown in FIG. 24D, after cleaning by this dipping method, shot blasting is performed to roughen the cylinder bore surface Y to slightly deform the cylinder bore surface Y to roughen the surface. The Cooland Z remaining in the inside of the battery jumps out. In the subsequent step of spraying the coating, the oil component expands and oozes out to the cylinder bore surface due to heating when spraying the coating. Thus, it was found that when the coating is formed by spraying while leaving the working oil such as Cooland that has come out on the cylinder bore surface, the adhesion of the coating is significantly reduced.
[0010]
It is common sense in terms of cost to repeatedly use a cleaning solution such as an organic solvent or an alkaline degreasing solution for cleaning the cylinder bore surface. Therefore, contamination of the cleaning liquid is unavoidable, and the cylinder bore surface cleaned with the cleaning liquid used for the second and subsequent times is not completely clean. In view of this, a technique has been adopted in which a plurality of cleaning tanks containing cleaning liquid are provided to reduce the dirt of the cleaning liquid. However, as the number of workpieces to be cleaned increased, contamination of the cleaning liquid contained in the final cleaning tank was inevitable. Therefore, there has been a problem that the cylinder bore surface cannot be completely cleaned due to contamination of the cleaning liquid. As a result, since the coating is formed by spraying on the cylinder bore surface where the dirt remains, there is a problem that the adhesion of the formed coating is lowered.
[0011]
The cylinder bore surface described here is not only for the cylinder bore surface but also for drilling by drilling a cast product having a cast hole and cleaning the side wall surface of the hole by a conventional method. This is a problem that occurs equally when a film is formed.
[0012]
Accordingly, an object of the present invention is to provide a method for treating a cylinder bore surface, which is performed as a pretreatment for forming a coating, and can improve the adhesion of the coating formed on the cylinder bore surface as compared with the prior art. There is to do.
[0013]
Further, the object of the present invention is to provide a method for treating a perforated side wall surface, which is performed as a pretreatment for forming a film and can improve the adhesion strength of the film formed as compared with the prior art. It is in.
[0014]
[Means for Solving the Problems]
In order to improve the adhesion strength of the film, the present inventors thought that, above all, it was necessary not only to roughen the cylinder bore surface but also to clean the cylinder bore surface cleanly. To that end, we have sought a method to reliably remove working oil such as coolant remaining in the inside of the casting hole opened in the cylinder bore while at the same time roughening the cylinder bore surface on which the film is formed. As a result of the study, it was considered that if the technique of injecting high-pressure water onto the cylinder bore surface was used, the cylinder bore surface could be roughened, and at the same time, the working oil such as Cooland remaining in the casting cavity could be removed.
[0015]
On the other hand, Japanese Patent Publication No. 2586986 discloses a method of cleaning a cylinder bore surface by injecting high-pressure water onto the cylinder bore surface. The inventors examined this patent publication No. 2586986. And the amount of flowing water per nozzle calculated from the pressure of the high pressure water and the diameter of the nozzle described in claim 2 and claim 5 of patent publication No. 2586986 is approximately 0.31 to 0.71 L / min, As a result, it has been recognized that this amount of flowing water cannot effectively remove the working oil such as Cooland that has accumulated inside the casting hole opened in the cylinder bore surface.
[0016]
Further, the inventors of the present invention have, in the nozzle inner diameter described in claim 5, a region where the surface of the high pressure water is concentrated and the surface is cut, and a region where the energy of the high pressure water is not concentrated and the surface is not cut much. Appears in stripes, and the cylinder bore surface cannot be uniformly roughened.
[0017]
As a result of intensive research, the inventors have introduced a high-pressure water injection device having a high-pressure water injection nozzle into the internal space of the cylinder bore formed in the cylinder block as a first invention. The high pressure water injection nozzle directed toward the cylinder bore surface of the cylinder bore is rotated from the high pressure water injection nozzle to the cylinder bore surface while moving the internal space of the cylinder bore in the axial direction while rotating about the axis of the cylinder bore. In the method for treating a cylinder bore surface, in which high pressure water is injected into the cylinder bore surface to clean and roughen the cylinder bore surface, the internal diameter of the high pressure water injection nozzle is 0.30 to 0.44 mm, and is injected from the high pressure water injection nozzle The amount of high-pressure water is 2.3 to 5.6 L / min per one high-pressure water injection nozzle, and the high-speed water injection nozzle moves in the axial direction. It invented a method of processing the cylinder bore surface, which is a 1.0～8.0Mm / sec.
[0018]
In addition, as a second invention, the present inventors introduced the high-pressure water injection nozzle into the inner space of the perforations formed in a columnar shape using a high-pressure water injection device having a high-pressure water injection nozzle, The high-pressure water spray nozzle directed toward the side wall surface is rotated about the axis of the perforation as the center of rotation, and the internal space of the perforation is moved in the axial direction. In the method for treating a perforated side wall surface, in which water is injected to clean and roughen the side wall surface, the high-pressure water injection nozzle has an inner diameter of 0.30 to 0.44 mm and is injected from the high-pressure water injection nozzle. The amount of water is 2.3 to 5.6 L / min per one high-pressure water injection nozzle, and the moving speed in the axial direction of the high-pressure water injection nozzle is 1.0 to 8.0 mm / sec. Invented a method for treating the perforated side wall surface.
[0019]
In addition, 2nd invention is the invention which applied the processing method of the cylinder bore surface of 1st invention to the side wall surface of the perforation formed in the column shape, without limiting the object of surface treatment to a cylinder bore surface. Accordingly, the description of the cylinder bore surface processing method in the following description is basically applicable to the second invention as it is.
[0020]
[Effects of the Invention]
In the method for treating a cylinder bore surface according to the present invention, the high pressure water injection nozzle directed toward the cylinder bore surface is rotated about the axis of the cylinder bore while the internal space of the cylinder bore is moved in the axial direction. Inject high pressure water into
[0021]
In this case, the amount of high-pressure water sprayed from the high-pressure water spray nozzle is 2.3 to 5.6 L / min per high-pressure water spray nozzle, and the moving speed of the high-pressure water spray nozzle in the axial direction is 1.0 to 8 By setting the thickness to 0.0 mm / second, the surface of the cylinder bore surface can be efficiently and finely eroded and removed. As a result, minute irregularities can be formed on the side wall surface of the cylinder bore formed in a cylindrical shape, that is, the cylinder bore surface, and the surface can be efficiently roughened, and the surface of the cylinder bore surface can be efficiently cleaned. Furthermore, it is possible to remove the working oil such as Cooland that has entered the inside of the casting hole opened in the cylinder bore surface, thereby making the cylinder bore surface a clean cylinder bore surface.
[0022]
In the case where the amount of the high-pressure water described above is 2.3 to 5.6 L / min per high-pressure water injection nozzle and the moving speed in the axial direction of the high-pressure water injection nozzle is 1.0 to 8.0 mm / sec. By setting the inner diameter of the high-pressure water nozzle to 0.30 to 0.44 mm, the area where the impact energy of high-pressure water is concentrated and cut and the area where the impact energy of high-pressure water is not concentrated and consequently are not cut much Can be avoided, and the cylinder bore surface can be evenly cut and roughened to be cleaned.
[0023]
Further, according to the method for processing a side wall surface of a perforation according to the present invention, the surface of the side wall surface of the perforation can be efficiently and finely cut to remove erosion as in the first aspect of the invention. As a result, fine irregularities can be formed on the side wall surface of the perforation to efficiently roughen the surface, and the surface of the side wall surface of the perforation can be efficiently made a clean surface. Furthermore, it is possible to make the side wall surface a clean side wall surface by removing working oil such as Cooland that has entered the inside of the casting hole opened in the side wall surface of the perforation.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a method for treating a cylinder bore surface according to the present invention will be described. The cylinder bore surface processing method of the present invention uses a high-pressure water injection device having a high-pressure water injection nozzle to introduce the high-pressure water injection nozzle into the internal space of the cylinder bore formed in the cylinder block and direct it toward the cylinder bore surface of the cylinder bore. While rotating the high pressure water injection nozzle about the axis of the cylinder bore as the center of rotation, while moving the internal space of the cylinder bore in the axial direction, high pressure water is injected from the high pressure water injection nozzle onto the cylinder bore surface to clean and roughen the cylinder bore surface. In the cylinder bore surface treatment method, the internal diameter of the high-pressure water injection nozzle is 0.30 to 0.44 mm, and the amount of high-pressure water injected from the high-pressure water injection nozzle is 2.3 to 5. 6 L / min, and the axial movement speed of the high-pressure water injection nozzle is 1.0 to 8.0 mm / sec.
[0025]
Here, the high-pressure water injection apparatus is an apparatus that can generate high-pressure water with a high-pressure pump and inject this high-pressure water from a high-pressure water injection nozzle. In the cylinder bore surface processing method of the present invention, a high pressure water injection nozzle having an inner diameter of 0.30 mm to 0.44 mm can be introduced into the internal space of the cylinder bore, and the cylinder bore surface with the introduced high pressure water injection nozzle facing the cylinder bore surface. The water amount of 2.3 to 5.6 L / min can be injected from the high pressure water injection nozzle while rotating about the axis of the shaft and moving in the axial direction at a speed of 1.0 to 8.0 mm / sec. A high pressure water injection device can be used. Such a high-pressure injection device can be configured by a known technique.
[0026]
For example, a high-pressure pump that generates high-pressure water, a nozzle body having a high-pressure water injection nozzle having an inner diameter of 0.30 to 0.44 mm, a manipulator that rotates and moves the nozzle body, and high-pressure water that derives high-pressure water from the high-pressure pump It can comprise using piping and another member. The nozzle body generally includes two high-pressure water spray nozzles, but is not limited to two.
[0027]
In the case of using the high-pressure water injection apparatus having the above-described configuration, a nozzle body having a high-pressure water injection nozzle having an inner diameter of 0.30 to 0.44 mm is operated by a manipulator to introduce the nozzle body into the internal space of the cylinder bore. The nozzle body is rotated about the axis of the cylinder bore and moved in the axial direction at a speed of 1.0 to 8.0 mm / sec. It can be rotated as the center of rotation and moved in the axial direction at a speed of 1.0 to 8.0 mm / sec. And while moving the nozzle body in the axial direction while rotating the nozzle body in this way, it is possible to adjust the high pressure pump and eject high pressure water from 2.3 to 5.6 L / min from the high pressure water injection nozzle.
[0028]
In this case, the distance between the high-pressure water injection nozzle and the cylinder bore surface can be the distance normally used in the high-pressure water injection process (water jet). It can be about 8-20 mm, preferably 10-15 mm.
[0029]
While rotating the high-pressure water jet water nozzle in the axial direction and moving it in the axial direction at a speed of 1.0 to 8.0 mm / sec, high pressure water of 2.3 to 5.6 L / min is supplied to the cylinder bore surface. By hitting, the cylinder bore surface can be efficiently and moderately cut.
[0030]
When the cylinder bore surface is a cylinder bore surface provided on a cylinder block made of an aluminum alloy, the surface of the cylinder bore surface is cut so that the depth of the deepest portion of each concave and convex portion forming the surface is 0.05 mm or more on average. It is preferable to set so as to.
[0031]
The cylinder bore surface is cut and roughened to an extent that the depth of the deepest part of each recess is 0.05 mm or more on average, thereby improving the adhesion of the film formed in the subsequent process. Can be improved. Further, when the depth of the recesses is set to 0.05 mm or more on the average, the working oil such as the coolant entering the inside of the casting hole opened in the cylinder bore surface can be surely removed.
[0032]
Therefore, in the cylinder bore surface processing method of the present invention, it is preferable to adjust the flow rate and moving speed of the high-pressure water so that the average depth of the recesses is 0.05 mm or more.
[0033]
Moreover, the rotation speed of a high pressure water injection nozzle can be about 100-1000 rpm (roll per minute), and it is preferable to set it as 200-650 rpm. The moving speed in the circumferential direction of the high-pressure water ejected from the high-pressure water injection nozzle is generally defined by the rotational speed. Therefore, by setting the number of rotations of the high-pressure water spray nozzle suitable for the moving speed in the axial direction of the high-pressure water spray nozzle, the depth of the deepest part of each recess is 0.05 mm on average. The cylinder bore surface can be cut up to.
[0034]
Moreover, the pressure of the high-pressure water injected from the high-pressure water injection nozzle can be approximately 172 to 483 MPa, preferably 206 to 415 MPa. In the cylinder bore surface processing method of the present invention, the cylinder bore surface is cleaned and roughened by finely removing the surface of the cylinder bore surface by impact energy of the jetted high pressure water. In this case, the impact energy can be adjusted not only by the flow rate of the high-pressure water but also by the ejection pressure of the high-pressure water. Therefore, by appropriately adjusting the pressure of the high-pressure water, the impact energy of the high-pressure water can be adjusted, and therefore the degree of cutting of the surface of the cylinder bore surface that is erosion-removed by the high-pressure water can be adjusted.
[0035]
In the cylinder bore surface treatment method of the present invention, the inner diameter of the high-pressure water injection nozzle is set to 0.30 to 0.44 mm. When the inner diameter of the high-pressure water injection nozzle is reduced, the area of the irradiated area where the impact energy of high-pressure water is concentrated (hereinafter referred to as “the central irradiated area” as appropriate) is reduced. As the value of is increased, the area of the central irradiated region where the impact energy is concentrated is increased accordingly.
[0036]
In the cylinder bore surface processing method of the present invention, since the high-pressure water spray nozzle is moved in the axial direction while rotating, if the internal diameter of the high-pressure water spray nozzle is too small, a gap is formed between the central irradiated regions adjacent in the axial direction. Will occur. In addition, the degree of cutting increases in this gap area (hereinafter referred to as “gap area” as appropriate) and the central irradiated area. As a result, a central irradiated region having a large degree of cutting and a gap region having a small degree of cutting are alternately formed in stripes on the cylinder bore surface.
[0037]
In this case, the gap region where the degree of cutting is small is not sufficiently roughened. As a result, in the gap region, the adhesiveness of the film formed by thermal spraying in the subsequent process may be insufficient.
[0038]
In the cylinder bore surface processing method of the present invention, by setting the inner diameter of the high-pressure water jet nozzle to approximately 0.30 to 0.44 mm, the central irradiated region having a large degree of cutting and the gap region having a small degree of cutting are provided. Can be prevented, and the cylinder bore surface can be uniformly cut.
[0039]
In addition, pure water can also be used for the high pressure water injected from a high pressure water injection nozzle, and normal tap water and industrial water can also be used. Further, an alkali cleaning solution such as sodium carbonate water, a degreasing solution, or the like can be used.
[0040]
As described above, the cylinder bore surface processing method of the present invention finely cuts the cylinder bore surface, so that it is possible to clean the work oil such as the work oil adhering to the cylinder bore surface and the coolant such as the coolant entering the casting cavity. Can do. That is, a clean cylinder bore surface can be formed. Further, since the cylinder bore surface is finely cut, minute irregularities can be formed on the cylinder bore surface. By using the cylinder bore processing method of the present invention, the surface roughness of the cylinder bore surface can be made approximately 30 to 50 Rz in terms of the surface roughness of the old JIS. Here, the surface roughness of the old JIS refers to the surface roughness specified in 1982.
[0041]
This numerical value is slightly smaller than the case of roughening by shot blasting. Therefore, after the cylinder bore surface treatment method of the present invention is applied to the cylinder bore surface, the cylinder bore surface is properly cleaned and roughened even when the cylinder bore surface is dried and sprayed as it is to form a coating. Therefore, the formed film can obtain sufficient adhesion.
[0042]
The high-pressure water injection nozzle can be reciprocated in the axial direction to repeat the injection of high-pressure water onto the cylinder bore surface an appropriate number of times.
[0043]
Further, after the cylinder bore surface treatment method of the present invention, the cylinder bore surface can be further roughened by performing shot blasting as necessary.
[0044]
Further, the cylinder bore surface treatment method of the present invention uses a high-pressure water injection device in place of the conventional cleaning tank, so that the cost of installing a cleaning tank and consuming a large amount of cleaning liquid can be eliminated.
[0045]
FIG. 22 shows a process of forming a coating by spraying on the cylinder bore surface when the method for treating a cylinder bore surface of the present invention is used.
[0046]
First, before performing thermal spraying for forming a film on the cylinder bore surface, the cylinder bore surface processing method of the present invention is performed. By this cylinder bore surface treatment method, the cylinder bore surface is cleaned and roughened at the same time. In the cylinder bore surface processing method of the present invention, high pressure water injection is performed, so the cylinder bore surface is air-dried. Then, thermal spraying is performed on the dried cylinder bore surface to form a film on the cylinder bore surface. Thereafter, the cylinder bore surface on which the film is formed can be cooled, and post-processing such as honing can be performed.
[0047]
As described above, after the cylinder bore surface is air-dried, the cylinder bore surface can be further roughened by shot blasting in some cases. Then, after the cylinder bore surface is dried by a method such as air cleaning, a coating can be formed on the cylinder bore surface by spraying the cylinder bore surface. Thereafter, the cylinder bore surface on which the film is formed can be cooled to perform post-processing.
[0048]
The cylinder bore surface treatment method of the present invention can be performed not only as a pretreatment for forming a film by thermal spraying but also as a pretreatment for forming a film by dipping, slurry-like substance coating, impregnation, or the like. is there.
[0049]
The cylinder bore surface treatment method can be applied to other than the cylinder bore surface as described above. That is, the present invention can be applied as it is not to the cylinder bore surface but also to the side wall surface of the perforation formed in a columnar shape. Therefore, as for the contents of the embodiment, the contents described as the processing method of the cylinder bore surface can be read as the processing method of the side wall surface of the perforation formed in a columnar shape.
[0050]
【Example】
(Machining amount measurement test and film adhesion strength test)
The cylinder bore surface treatment method of the present invention was carried out, and a measurement test of the amount of cutting and an adhesion strength test of the film were conducted.
[0051]
(1) Explanation of Example
The outline of the high-pressure water jetting apparatus used in the measurement test of the amount of cut and the adhesion strength test of the film, and an example carried out in performing these tests will be described with reference to FIGS.
[0052]
The high-pressure water injection device 100 includes a high-pressure water injection pump 10, a high-pressure water pipe 20, a manipulator 30, a nozzle body 40 including two high-pressure water injection nozzles 50, and the like. The internal diameter of the high-pressure water injection nozzle 50 is φ0.38 mm. In the various tests described below, the configuration of the high-pressure water injection device is the same.
[0053]
As shown in FIGS. 1 and 2, the manipulator 30 is operated to introduce the nozzle body 40 into the internal space of the cylinder bore 120, and the nozzle body 40 is rotated about the axis of the cylinder bore 120 as a rotation center and moved in the axial direction. The high-pressure water injection nozzle 50 was rotated about the axis of the cylinder bore 120 as the center of rotation and moved in the axial direction. Then, the high pressure water generated by the high pressure water pump 10 is sprayed from the high pressure water injection nozzle 50 onto the cylinder bore surface 130 while being moved in the axial direction while rotating the high pressure water injection nozzle 50, and the cylinder bore surface 130 is cleaned and roughened. did.
[0054]
In this embodiment, the number of rotations of the high-pressure water spray nozzle 50 is 650 rpm, and the moving speed in the axial direction of the high-pressure water spray nozzle 50 is 3 mm / second.
[0055]
In the high-pressure water injection device 100 used in this example, a plurality of high-pressure water flow rates were set in the range of 2.3 to 5.6 L / min. The relationship between the pressure of the high-pressure water pump and the flow rate of high-pressure water from the high-pressure water injection nozzle in this example is 3.07 L / min when 205 MPa and 3.32 L / min when 245 MPa and 3 when 276 MPa. It was 3.76 L / min when it was 0.55 L / min, 310 MPa, 3.97 L / min when it was 345 MPa, and 4.16 L / min when it was 380 MPa.
[0056]
(2) Machining amount measurement test
The example mentioned above was implemented and the relationship between the pressure of a high-pressure water pump and the amount of cutting of a cylinder bore surface was tested. That is, the inner diameter of the high-pressure water injection nozzle was φ0.38 mm, the rotation speed of the high-pressure water injection nozzle 50 was 650 rpm, and the moving speed in the axial direction of the high-pressure water injection nozzle was 3 mm / second. In this measurement test, the high-pressure water injection nozzle was moved twice in the axial direction along the entire length of the cylinder bore surface.
[0057]
The cylinder bore surface subjected to the measurement test is a cylinder bore surface provided on a cylinder block made of aluminum alloy die casting, JIS H5302 ADC12. The length of the cylinder bore in the axial direction was 135 mm, and the inner diameter of the cylinder bore was φ82 mm. On the surface of the cylinder bore surface, there is an average of 1 cm in diameter of φ0.5 mm. ² There were 0.2 per hit.
[0058]
The pressure of the high-pressure water pump was set to a plurality of pressures such as 205 MPa, 245 MPa, 276 MPa, 310 MPa, 345 MPa, and 380 MPa, and the cylinder bore surface treatment method of the present invention was performed. The amount of machining on the cylinder bore surface at each pressure was measured. Here, normal tap water was used as high-pressure water.
[0059]
The flow rate of high-pressure water from the high-pressure water injection nozzle at this time is as described above.
[0060]
FIG. 3 shows the relationship between the pressure of the high-pressure water pump and the amount of machining (average depth of machining) on the cylinder bore surface. As a result of this measurement test, the relationship between the pressure of the high-pressure pump, the amount of high-pressure water and the amount of cut was as follows. When the pressure is 205 MPa and the amount of water is 3.07 L / min, 0.02 mm when the pressure is 245 MPa and 3.32 L / min, 0.043 mm when the pressure is 305 MPa and 3.55 L / min, 0.075 mm when the pressure is 3.55 L / min and 3. It was 0.11 mm at 76 L / min, 0.15 mm at 3.97 L / min at 345 MPa, and 0.21 mm at 4.16 L / min at 380 MPa.
[0061]
Note that the measurement of the amount of cutting is a numerical value estimated from a chart obtained by simultaneously applying a portion where the processing method of the cylinder bore surface according to this embodiment is performed and a portion where the processing method has not been performed to a surface shape measuring instrument. Therefore, this numerical value is not the average value of the depth of the deepest part of the concave portions of the individual irregularities described above, but the average value of the cut depth.
[0062]
FIGS. 4 and 5 show enlarged photographs of the cylinder bore surface when the pressure is 276 MPa and the amount of water is 3.55 L / min and the surface of the cylinder bore surface is cut by 0.075 mm. FIG. 5 is an enlarged view of FIG.
[0063]
4 and 5, it can be seen that the surface of the cylinder bore surface is finely cut and unevenness is formed. At this time, the surface roughness of the cylinder bore surface was approximately 40 Rz as the surface roughness of the old JIS.
[0064]
(3) Adhesion strength test of film
Furthermore, the adhesion strength of the coating formed by thermal spraying on the cylinder bore surface processed in the above-described embodiment was measured. That is, the inner diameter of the high pressure water injection nozzle was φ0.38 mm, the rotation speed of the high pressure water injection nozzle 50 was 650 rpm, and the moving speed in the axial direction of the high pressure water injection nozzle was 3 mm / second. The pressure of the high-pressure water pump, the amount of high-pressure water, and multiple types of high-pressure water were set. In this adhesion strength test, the high-pressure water injection nozzle was moved twice in the axial direction along the entire length of the cylinder bore surface.
[0065]
The cylinder bore surface subjected to the adhesion strength test is a cylinder bore surface provided on a cylinder block made of aluminum alloy die cast, JIS H5302 ADC12. The length of the cylinder bore in the axial direction was 135 mm, and the inner diameter of the cylinder bore was φ82 mm. On the surface of the cylinder bore surface, there is an average of 1 cm in diameter of φ0.5 mm. ² There were 0.2 per hit.
[0066]
For comparison, a coating formed by spraying on a cylinder bore surface roughened by shot blasting as test example 1 and a cylinder bore surface roughened by shot without cleaning as test example 2 for comparison. The adhesion strength was measured. Therefore, Test Example 3 to Test Example 9 are examples in which the cylinder bore surface is processed in this example. Table 1 shows the conditions of each test example.
[0067]
[Table 1]

[0068]
In Table 1, the type of high-pressure water refers to the type of high-pressure water ejected from the high-pressure water jet nozzle in this embodiment. The pressure means the pressure of the high-pressure water pump, and the amount of water means the amount of high-pressure water jetted from the high-pressure water jet nozzle. The blast material means particles used for shot blasting, and alumina particles were used in this test. Alumina # 24 was used as the alumina particles. The thermal spray material sprayed on the cylinder bore surface was all Fe-1% C iron-based material.
In Test Example 1, the cylinder bore surface was cleaned three times by dipping in an organic solvent cleaning solution. Thereafter, the cylinder bore surface is roughened by shot blasting with alumina particles. Then, the cylinder bore surface was dried by an air cleaning method, and then a Fe-1% C iron-based material was sprayed onto the cylinder bore surface to form a film.
[0069]
In Test Example 2, the cylinder bore surface is roughened by shot blasting with alumina particles without cleaning. Then, the cylinder bore surface was dried by an air cleaning method, and then a Fe-1% C iron-based material was sprayed onto the cylinder bore surface to form a film.
[0070]
In Test Example 3 to Test Example 7, this example was implemented to treat the cylinder bore surface. That is, the cylinder bore surface processing method of the present invention was carried out. The cylinder bore surface was air dried. Thereafter, an iron base material of Fe-1% C was sprayed on the cylinder bore surface to form a coating on the dried cylinder bore surface. In Test Examples 3 to 5, tap water was used as high-pressure water, and in Test Examples 6 and 7, sodium carbonate water was used as high-pressure water. The pressure and the amount of water are as shown in Table 1.
[0071]
In Test Example 8 and Test Example 9, after the cylinder bore surface was processed and the cylinder bore surface was air-dried, the cylinder bore surface was further roughened by shot blasting with alumina particles. And after drying the cylinder bore surface by air cleaning method, a coating was formed on the cylinder bore surface by spraying Fe-1% C iron-based material on the cylinder bore surface.
In each of Test Examples 1 to 9, the cylinder bore surface on which the film was formed was cooled and post-processing such as honing was performed.
[0072]
The result of the film adhesion strength test is shown in FIG. The adhesion strength of the film was measured by a shearing method. In FIG. 6, the bar graph indicates the average value of the adhesion strength, and the arrow indicates the variation in the adhesion strength.
[0073]
Test Example 1 has an average value of adhesion strength that is substantially the same as that of Examples 3 to 9 of the present invention, but it can be seen that the variation in adhesion strength is remarkably large. As described above, in Test Example 1, the variation in the adhesion strength of the film is large because the working oil such as Cooland remaining in the casting hole cannot be removed by cleaning, and the oil content of the working oil on the cylinder bore surface is completely cleaned. This is considered to be due to the difference between the region where the working oil is ejected from the casting cavity by shot blasting or the working oil oozes out by spraying and is contaminated with oil.
[0074]
When only the shot blast was applied to the cylinder bore surface without cleaning as in Test Example 2, the average value of the adhesion strength of the coating itself was low, and the variation in the adhesion strength was large.
[0075]
In addition, the external appearance photograph of the cast hole which appeared on the cylinder bore surface of Test Example 2 is shown in FIG. 7, FIG. 8, and FIG. The casting hole of FIG. 7 is a casting hole of approximately φ0.65 mm. The casting hole in FIG. 8 is a casting hole of approximately 1.1 × 0.4 mm. The casting hole in FIG. 9 is a 1.8 × 0.6 mm casting hole.
[0076]
Further, the adhesion strength of the film in the vicinity of the casting hole in the region where the number of casting holes on the cylinder bore surface of Test Example 1 was significantly large and the adhesion strength of the film in the region where no casting hole was found were measured. Again, this was measured by the shear method. FIG. 10 shows the measurement results.
[0077]
It can be seen that the adhesion strength of the film in the vicinity of the casting hole is significantly lower than the adhesion strength of the film in the region where there is no casting hole. Thus, in Test Example 1, the adhesion strength of the film is greatly different between the region near the casting hole and the region without the casting hole, because the region near the casting hole is contaminated with oil.
[0078]
Test Examples 3 to 9 are examples using the cylinder bore surface processing method of this example. Test Example 8 and Test Example 9 are examples in which shot blasting was performed after the cylinder bore surface processing method of the present example was performed.
[0079]
Test Example 3 has a smaller variation in adhesion strength than Test Example 1, but is larger than Test Examples 4 to 9. The reason why the variation is smaller than in Test Example 1 is considered to be because oil can be removed more uniformly than in Test Example 1. Further, the reason why the variation is larger than in Test Examples 4 to 9 is considered that the pressure of the high-pressure water pump is low and the amount of high-pressure water is small. That is, according to the previous measurement test of the amount of cut, it is 0.02 mm when 205 MPa and 3.07 L / min. Therefore, it is considered that the oil content in the cast hole was not sufficiently removed.
[0080]
In Test Example 4 to Test Example 9, the average value of the adhesion strength is substantially the same as that of Test Example 1, but the variation in adhesion strength is significantly smaller than that of Test Example 1. This is considered to be because for Test Example 4 to Test Example 9, the amount of oil on the inside of the casting cavity was reliably removed as compared with Test Example 1 by increasing the amount of surface cutting.
[0081]
Specifically, Test Example 3 to Test Example 5 are the same under the same conditions except that the pressure of the high-pressure water pump and the amount of high-pressure water are different. The type of high-pressure water is tap water. It can be seen that as the pressure and the amount of water increase, the average value of the adhesion strength increases and the variation in the adhesion strength decreases. This is presumably because the increase in the amount of cutting increases the roughness of the surface, improves the adhesion strength, and removes more oil remaining in the casting cavity.
[0082]
In addition to the tests performed under the conditions shown in Table 1, the surface was cut to 0.21 mm under the conditions of tap water as the type of high-pressure water, the pressure as 380 MPa, and the amount of water as 4.16 L / min per high-pressure water injection nozzle. The adhesion strength was also confirmed in this case, but was not significantly different from that in Test Example 5.
[0083]
Test Example 6 and Test Example 7 are examples using sodium carbonate water used in alkaline cleaning as high-pressure water. Test Example 6 differs only in the type of high-pressure water, and the subsequent conditions are the same as Test Example 4. Similarly, Test Example 7 differs only in the type of high-pressure water, and the subsequent conditions are the same as Test Example 5. When Test Example 4 and Test Example 6 are compared, the average value of the adhesion strength is slightly improved in Test Example 6, and the variation in adhesion strength is also improved in Test Example 6. Comparing Test Example 5 and Test Example 7, the average adhesion strength was slightly better in Test Example 5, and the variation in adhesion strength was slightly smaller in Test Example 5. In any case, it can be seen that there is not much difference between using tap water and using sodium carbonate water.
[0084]
Test Example 8 and Test Example 9 are examples in which shot blasting was performed after Test Example 4 and Test Example 5. It can be seen that the average value of the adhesion strength and the variation in the adhesion strength are slightly improved.
[0085]
Although this test is a test performed on the cylinder bore surface, even if the cylinder bore surface is not particularly formed, an equivalent result can be obtained as long as the side wall surface of the perforated column is formed.
[0086]
(Cavity observation test)
In this observation test, the cylinder bore surface was processed using the cylinder bore surface processing method of the present invention, and the cross section of the cast hole was observed when a sprayed coating was formed. In addition, ADC12 was used for the material which comprises a cylinder bore surface.
[0087]
In this observation test, an artificial casting hole having an inner diameter of φ0.8 mm was provided as a casting hole opened on the cylinder bore surface. The cylinder bore surface treatment method was set in two conditions: the inner diameter of the high-pressure water injection nozzle was φ0.381 mm, and the amount of water from the high-pressure water injection nozzle was 3.07 L / min and 4.16 L / min. The pressure of the high-pressure water pump at this time was 380 MPa. Further, the moving speed in the axial direction of the high-pressure water injection nozzle was set such that the amount of water was 3.07 L / min, 2 mm / sec, and the amount of water was 4.16 L / min, 4 mm / sec. Further, the number of rotations of the high-pressure water injection nozzle was 650 rpm. The high-pressure water injection nozzle was moved once in the axial direction along the entire length of the cylinder bore surface. The length of the cylinder bore in the axial direction was 135 mm, and the inner diameter of the cylinder bore was φ82 mm.
[0088]
Further, after treating the surface of the cylinder bore surface under the above conditions, an iron-based film was formed by thermal spraying. A film was formed so that the thickness was 0.1 mm.
[0089]
11 and 12 show photographs of the cross section of the artificial casting hole when the film is formed in this way. FIG. 11 is a photograph of a cross section when the water amount is 3.07 L / min and the moving speed is 2 mm / sec. FIG. 12 is the case where the water amount is 4.16 L / min and the moving speed is 4 mm / sec. FIG.
[0090]
It can be seen from FIGS. 11 and 12 that the opening of the artificial casting cavity is crushed and reduced by carrying out the cylinder bore surface treatment method of the present invention. This is a high-pressure fluid that efficiently removes the cylinder bore surface, cleans the surface of the cylinder bore surface by cutting it finely, and simultaneously moves a large amount of fluid over the artificial casting cavity at a constant moving speed. This is because the edge portion of the opening of the cast hole is plastically flowed.
[0091]
When a low carbon iron alloy is thermally sprayed to form a film having a thickness of 0.1 to 0.2 mm, it is found that a cast hole having an inner diameter of φ0.5 mm or less can be filled with a film by thermal spraying. Has been issued. Therefore, a countermeasure for a cast hole having an inner diameter of φ0.5 to 0.8 mm has been a problem.
[0092]
In the processing method of the cylinder bore surface of the present invention, even when the water amount is set to 3.07 L / min and the moving speed is set to 2 mm / sec, the water amount is set to 4.16 L / min and the moving speed is set to 4 mm / sec. It can be seen that the edge portion of the opening of the casting hole is plastically flowed and cleaned while closing the opening.
[0093]
For reference, FIG. 13 shows a photograph of a cross section of the artificial casting cavity when the cylinder bore surface within the range of the conditions described in claims 2 and 5 of Japanese Patent No. 2586986 is processed. The processing conditions of the cylinder bore surface will be described more specifically. The inner diameter of the high pressure water injection nozzle is φ0.15 mm, the amount of water is 0.57 L / min, the moving speed in the axial direction of the high pressure water injection nozzle is 2 mm / second, and the high pressure water injection The number of rotations of the nozzle was 650 rpm. Here, the inner diameter of the artificial casting hole provided on the cylinder bore surface was 0.6 mm, and the coating by thermal spraying was formed so that the film thickness was 0.3 mm. When the cylinder bore surface is processed under this condition, it can be seen that no change occurs in the opening.
[0094]
(Measurement test of aperture reduction rate)
In this measurement test, an artificial casting hole with an inner diameter of φ0.8 mm is provided as a casting hole opened on the cylinder bore surface, and how much the opening is reduced by injecting high-pressure water onto the cylinder bore surface, that is, how much is closed. Was measured. In addition, ADC12 was used for the material which comprises a cylinder bore surface.
[0095]
The setting conditions of the processing method of the cylinder bore surface were such that the inner diameter of the high-pressure water injection nozzle was φ0.381 mm, and the number of rotations of the high-pressure water injection nozzle was 650 rpm. A plurality of amounts of high-pressure water from the high-pressure water injection nozzle and moving speeds of the high-pressure water injection nozzle were set. That is, four types of moving speeds of the high-pressure water jet nozzle were set: 1 mm / second, 1.5 mm / second, 2 mm / second, and 4 mm / second. The amount of water from one high-pressure water injection nozzle was set to 2.17 L / min, 2.51 L / min, 3.07 L / min, 3.55 L / min, and 4.35 L / min. The high-pressure water injection nozzle was moved once in the axial direction along the entire length of the cylinder bore.
[0096]
The length of the cylinder bore in the axial direction was 135 mm, and the inner diameter of the cylinder bore was φ82 mm.
[0097]
These results are shown in FIG. From these results, when the amount of water exceeds 3.07 L / min and the moving speed of the high-pressure water injection nozzle is 1 mm / sec, 1.5 mm / sec, 2 mm / sec, the inner diameter is φ0.8 mm It can be seen that the opening is closed and the diameter is 0.5 mm or less. Therefore, it is considered that the moving speed in the axial direction of the high-pressure water spray nozzle is preferably set to about 1 to 3 mm / second.
[0098]
(Irradiated area observation test)
Next, the relationship between the inner diameter of the high-pressure water jet nozzle and the area irradiated with high-pressure water, that is, the irradiated area was observed.
[0099]
15 and 16 show photographs of the cylinder bore surface when high-pressure water is injected within the range of the conditions described in claims 2 and 5 of Japanese Patent No. 2586986. FIG. 16 is an enlarged photograph of a part of FIG. FIG. 17 shows a photograph of the cylinder bore surface when the cylinder bore surface processing method of the present invention is executed.
[0100]
Here, specific conditions for injecting high-pressure water within the range of the conditions described in claims 2 and 5 of Japanese Patent No. 2586986 will be described. The inner diameter of the high-pressure water injection nozzle is φ0.15 mm, The pressure of the pump is 276 MPa, the amount of water is 0.57 L / min, the moving speed in the axial direction of the high pressure water injection nozzle is 2 mm / second, and the rotation speed of the high pressure water injection nozzle is 650 rpm. In the following description, the condition of Japanese Patent No. 2586986 refers to the condition described here.
[0101]
In claim 2 of Japanese Patent No. 2586986, the pressure is described as “between 25.000 psi and 60.000 psi”, and in claim 5, the inner diameter of the high-pressure water injection nozzle is defined as “0.005 inch to 0.006 inch”. Is described.
[0102]
On the other hand, the specific conditions of the present invention will be described. The inner diameter of the high pressure water injection nozzle is φ0.38 mm, the pressure of the high pressure water pump is 310 MPa, the amount of water is 3.76 L / min, and the axial direction of the high pressure water injection nozzle is The moving speed is 1.5 mm / second, and the rotation speed of the high-pressure water spray nozzle is 650 rpm. In the following description, the condition of the present invention refers to the condition described here.
[0103]
In any case, the axial length of the cylinder bore was 135 mm, and the inner diameter of the cylinder bore was φ82 mm. The high-pressure water injection nozzle was moved once in the axial direction along the entire length of the cylinder bore.
[0104]
When high pressure water is injected under the condition of Japanese Patent No. 2586986, it can be seen from FIGS. 15 and 16 that the cylinder bore surface has been processed into a stripe shape. In other words, it can be seen that there is unevenness in the way of processing. In contrast, when the cylinder bore surface is processed under the conditions of the present invention, it can be seen that there is no unevenness.
[0105]
This is presumably because when the treatment is performed under the conditions of Japanese Patent No. 2566986, the area of the irradiated region where the impact energy of the high-pressure water is concentrated is reduced because the inner diameter of the high-pressure water injection nozzle is small. On the other hand, when the treatment is performed under the conditions of the present invention, the area of the irradiated region where the impact energy of the high-pressure water is concentrated is moderately wide because the inner diameter of the high-pressure water injection nozzle is large. Conceivable.
[0106]
Here, a state of jetting high-pressure water, an irradiation pattern, and an energy pattern are shown in FIG. FIG. 18A shows the case of processing under the conditions of Japanese Patent No. 2586986, and FIG. 18B shows the case of processing under the conditions of the present invention.
[0107]
Thus, when processing under the conditions of Japanese Patent No. 2586986, the high pressure water injection nozzle is moved in the axial direction while rotating. There is a gap region (hereinafter referred to as “gap region” as appropriate) between the irradiation region (hereinafter referred to as “center irradiated region” as appropriate) and the central irradiated region of the high pressure water jet nozzle adjacent to this irradiated region in the axial direction. Will occur. The degree of cutting increases between the gap region and the central irradiated region. As a result, a central irradiated region having a large degree of cutting and a gap region having a small degree of cutting are formed in a stripe shape on the cylinder bore surface.
[0108]
On the other hand, when the cylinder bore surface is processed under the conditions of the present invention, the central irradiated region has an appropriate area, so that it is adjacent to the central irradiated region of the high-pressure water jet nozzle and the central irradiated region in the axial direction. There is no gap between the central irradiated region.
[0109]
Here, FIG. 19A shows the state of cutting of the cylinder bore surface when processed under the conditions of Japanese Patent No. 2586986, and FIG. 19B shows the state of cutting of the cylinder bore surface when processed under the conditions of the present invention. Indicates. As shown in FIG. 19A, when processing is performed under the conditions of Japanese Patent No. 2586986, a gap is generated between the central irradiated region and the adjacent central irradiated region, and a large swell is formed. In contrast, as shown in FIG. 19B, there is no swell when processing is performed under the conditions of the present invention.
[0110]
FIG. 20 shows a graph of the surface roughness of the cylinder bore surface processed here. 20A shows the surface roughness of the cylinder bore surface when treated under the conditions of Japanese Patent No. 2586986, and FIG. 20B shows the surface roughness of the cylinder bore surface when treated under the conditions of the present invention. .
[0111]
As shown in FIG. 20A, when processing was performed under the conditions of Japanese Patent No. 2586986, peaks and valleys were formed on the cylinder bore surface. In FIG. 20, the central irradiated region is indicated by (1), and the gap region is indicated by (2). The central irradiated area where the impact energy is concentrated becomes a valley, and the gap area forms a peak. In the case of processing in Japanese Patent No. 2586986, the surface roughness of the cylinder bore surface as a whole was able to obtain a value of about 40-60 Rz in the old JIS, but about 5-20 Rz about the mountain part which is the gap region. Only numerical values could be obtained. In addition, it has been confirmed by experience that the surface roughness that can provide the adhesion strength required for the sprayed coating is approximately 13 Rz in terms of the old JIS surface roughness. I can't get it.
[0112]
In the case of processing under the conditions of the present invention, there is no distinction between the central irradiated region and the gap region as shown in FIG. Therefore, no crests or troughs are formed, and there is no difference between the partial surface roughness of the central irradiated region and the gap region and the surface roughness of the entire cylinder bore surface. This is presumably because the surface of the entire cylinder bore surface was cut uniformly.
[0113]
As in the case of processing under the condition of Japanese Patent No. 2586986, when a crest and a trough are generated on the cylinder bore surface and there is a difference in the depth, it is necessary to smooth the surface of the cylinder bore surface in post-processing after spraying. Therefore, the thickness of the sprayed coating must be determined according to the deep valley. In addition to the increase in cycle time, this also increases the tensile residual stress in the film as the film thickness increases, which adversely affects the adhesion strength of the film.
[0114]
Furthermore, if there are peaks and valleys, the peaks may adversely affect the spraying on the valleys. This means that a blocking effect often referred to in thermal spraying construction appears. A photograph showing the cylinder bore surface on which the blocking effect appears is shown in FIG. The cylinder bore surface shown in FIG. 21 is obtained by spraying the cylinder bore surface shown in FIG. Thus, typical pores with a blocking effect are observed. This is not favorable for the quality of the coating.
[0115]
In the case of processing under the conditions of the present invention, the above-mentioned drawbacks can be avoided because no distinction is made between peaks and valleys.
[0116]
The above description can be applied not only to the cylinder bore surface but also to the side wall surface of the perforation formed in a columnar shape.
[0117]
【The invention's effect】
As a pretreatment for forming the coating, the coating cylinder bore surface and the perforated side wall surface of the present invention are processed using the cylinder bore surface processing method of the present invention and the perforated side wall surface processing method of the present invention, thereby improving the adhesion strength of the coating. Can be improved.
[Brief description of the drawings]
FIG. 1 is a view schematically showing an outline of a high-pressure water jetting apparatus used in a measurement test of a work amount and an adhesion strength test of a film.
FIG. 2 is a diagram showing an outline of a nozzle body of a high-pressure water jetting apparatus used in a measurement test of a work amount and an adhesion strength test of a film.
FIG. 3 is a graph showing the relationship between the pressure of the high-pressure water pump and the amount of machining on the cylinder bore surface.
FIG. 4 is an enlarged photograph of the cylinder bore surface when the pressure is 276 MPa and the amount of water is 3.55 L / min and the surface of the cylinder bore surface is cut 0.075 mm.
5 is an enlarged view of FIG. 4;
FIG. 6 is a diagram showing the results of a film adhesion strength test.
FIG. 7 is a photograph showing an appearance of a cast hole appearing on a cylinder bore surface.
FIG. 8 is a photograph showing an appearance of a cast hole appearing on a cylinder bore surface.
FIG. 9 is a photograph showing an appearance of a cast hole appearing on a cylinder bore surface.
FIG. 10 is a diagram showing the results of measuring the adhesion strength of a film in the vicinity of a casting hole in a region where the number of casting holes on the cylinder bore surface is significantly large and the adhesion strength of the film in a region where no casting hole is seen at all. .
FIG. 11 is a photograph of a cross section of an artificial cast hole when a film is formed, and is a photograph of a cross section when the amount of water is 3.07 L / min and the moving speed is 2 mm / sec.
FIG. 12 is a photograph of a cross section of an artificial cast hole when a film is formed, and is a photograph of a cross section when processing is performed at a water amount of 4.16 L / min and a moving speed of 4 mm / sec.
FIG. 13 is a cross-sectional photograph of an artificial casting hole when a film is formed, and the artificial casting hole when a cylinder bore surface within the range of the conditions described in claims 2 and 5 of Japanese Patent No. 2586986 is processed. FIG.
FIG. 14 is a diagram showing the results of an aperture reduction rate measurement test.
FIG. 15 is a photograph of a cylinder bore surface when high pressure water is injected within the range of the conditions described in claims 2 and 5 of Japanese Patent No. 2586986.
FIG. 16 is a photograph of a cylinder bore surface when high pressure water is injected within the range of the conditions described in claims 2 and 5 of Japanese Patent No. 2586986.
FIG. 17 is a photograph of a cylinder bore surface when the cylinder bore surface processing method of the present invention is executed.
FIG. 18 is a diagram showing a state of high-pressure water injection, an irradiation pattern, and an energy pattern. FIG. 18A shows the case of processing under the conditions of Japanese Patent No. 2586986, and FIG. 18B shows the case of processing under the conditions of the present invention.
FIG. 19 is a diagram showing a state of cutting of the cylinder bore surface. FIG. 19A shows the state of machining of the cylinder bore surface when processed under the conditions of Japanese Patent No. 2586986, and FIG. 19B shows the state of machining of the cylinder bore surface when processed under the conditions of the present invention.
FIG. 20 is a diagram showing a graph of the roughness of the treated cylinder bore surface. 20A shows the surface roughness of the cylinder bore surface when treated under the conditions of Japanese Patent No. 2586986, and FIG. 20B shows the surface roughness of the cylinder bore surface when treated under the conditions of the present invention. .
FIG. 21 is a photograph showing a cylinder bore surface on which a blocking effect appears.
FIG. 22 is a diagram showing a process for forming a film using the cylinder bore processing method of the present invention.
FIG. 23 shows a step of forming a film by spraying on a cylinder bore surface that is conventionally performed.
FIG. 24 is a view showing a state in which the Cooland remains in the casting cavity in the conventional process, and the Cooland pops out after shot blasting.
[Explanation of symbols]
X: Cast hole
Y: Cylinder bore surface
Z: Cooland
10: High pressure water injection pump
20: High pressure water piping
30: Manipulator
40: Nozzle body
50: High pressure water injection nozzle
100: High pressure water injection device
110: Cylinder block
120: Cylinder bore
130: Cylinder bore surface

Claims (7)

Using a high-pressure water injection device having a high-pressure water injection nozzle, the high-pressure water injection nozzle is introduced into the internal space of the cylinder bore formed in the cylinder block, and the high-pressure water injection nozzle directed toward the cylinder bore surface of the cylinder bore is connected to the cylinder bore. A cylinder bore surface that cleans and roughens the cylinder bore surface by injecting high-pressure water from the high-pressure water injection nozzle onto the cylinder bore surface while moving the inner space of the cylinder bore in the axial direction while rotating about the axis of the cylinder In the processing method of
The internal diameter of the high-pressure water injection nozzle is 0.30 to 0.44 mm,
The amount of high-pressure water sprayed from the high-pressure water spray nozzle is 2.3 to 5.6 L / min per one high-pressure water spray nozzle,
A method for treating a cylinder bore surface, wherein an axial moving speed of the high-pressure water spray nozzle is 1.0 to 8.0 mm / sec. 2. The cylinder bore surface treatment according to claim 1, wherein the depth of machining of the cylinder bore surface by the injection of the high-pressure water is such that the depth of the deepest portion of the concave and convex portions formed on the cylinder bore surface is 0.05 mm or more on average. Method. The method for treating a cylinder bore surface according to claim 1 or 2, wherein the rotation speed of the high-pressure water injection nozzle is 100 to 1000 rpm. The method for treating a cylinder bore surface according to claim 1, 2 or 3, wherein the pressure of the high-pressure water sprayed from the high-pressure water spray nozzle is 206 to 415 MPa. The cylinder bore surface processing method according to claim 1, wherein the cylinder block is an aluminum alloy cylinder block. Using a high-pressure water injection device having a high-pressure water injection nozzle, the high-pressure water injection nozzle is introduced into the inner space of the perforation formed in a columnar shape, and the high-pressure water injection nozzle directed toward the side wall surface of the perforation The high-pressure water is sprayed from the high-pressure water spray nozzle onto the side wall surface of the perforation while the inner surface of the perforation is moved in the axial direction while rotating about the axis of the shaft, and the side wall surface is cleaned and roughened. In the processing method of the perforated side wall surface,
The internal diameter of the high-pressure water injection nozzle is 0.30 to 0.44 mm,
The amount of high-pressure water sprayed from the high-pressure water spray nozzle is 2.3 to 5.6 L / min per one high-pressure water spray nozzle,
The method for treating a perforated side wall surface, wherein the high-speed water jet nozzle has an axial moving speed of 1.0 to 8.0 mm / sec. The perforation side according to claim 6, wherein the depth of the deepest portion of the concave and convex recesses formed on the side wall surface is 0.05 mm or more on average as the degree of cutting of the side wall surface of the perforation by the injection of the high-pressure water. Wall processing method.

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