JP2020186430A - Steel plate for ultrasonic bonding, high-strength steel plate for ultrasonic bonding, and ultrasonic bonding method - Google Patents
Steel plate for ultrasonic bonding, high-strength steel plate for ultrasonic bonding, and ultrasonic bonding method Download PDFInfo
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 108
- 239000010959 steel Substances 0.000 title claims abstract description 108
- 238000000034 method Methods 0.000 title claims description 28
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 30
- 238000005097 cold rolling Methods 0.000 claims abstract description 16
- 229910052751 metal Inorganic materials 0.000 claims description 20
- 239000002184 metal Substances 0.000 claims description 20
- 239000000203 mixture Substances 0.000 claims description 11
- 239000012535 impurity Substances 0.000 claims description 9
- 238000003825 pressing Methods 0.000 claims description 9
- 229910001315 Tool steel Inorganic materials 0.000 claims description 8
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 2
- 239000010960 cold rolled steel Substances 0.000 description 40
- 239000007769 metal material Substances 0.000 description 10
- 239000000463 material Substances 0.000 description 9
- 230000007423 decrease Effects 0.000 description 8
- 238000005304 joining Methods 0.000 description 6
- 239000002436 steel type Substances 0.000 description 6
- 238000005728 strengthening Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000005096 rolling process Methods 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 150000001247 metal acetylides Chemical class 0.000 description 4
- 239000006104 solid solution Substances 0.000 description 4
- 229910001567 cementite Inorganic materials 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 3
- 229910052758 niobium Inorganic materials 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 238000009864 tensile test Methods 0.000 description 3
- 230000009466 transformation Effects 0.000 description 3
- 229910052720 vanadium Inorganic materials 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 238000002788 crimping Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000005246 galvanizing Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 238000010191 image analysis Methods 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Abstract
Description
本発明は、超音波接合用鋼板、超音波接合用高強度鋼板及び超音波接合方法に関する。 The present invention relates to a steel sheet for ultrasonic bonding, a high-strength steel sheet for ultrasonic bonding, and an ultrasonic bonding method.
鋼板同士の接合方法として、溶接及びかしめ接合が主に用いられている。
しかしながら、これらの接合方法は、溶接時の熱影響によって接合部の靭性や強度が低下する上、接合部の変形も大きいため意匠性の面でも不利である。
他方、接合部に対する影響が少ない接合方法として、超音波接合が注目されており、ＡｌやＣｕなどの非鉄金属材同士の接合、非鉄金属材と鋼材との接合などのような異種金属間の接合に広く活用されつつある。
Welding and caulking are mainly used as methods for joining steel sheets.
However, these joining methods are disadvantageous in terms of design because the toughness and strength of the joint are lowered due to the influence of heat during welding and the joint is greatly deformed.
On the other hand, ultrasonic bonding is attracting attention as a bonding method that has little effect on the bonded portion, and bonding between dissimilar metals such as bonding between non-ferrous metal materials such as Al and Cu and bonding between non-ferrous metal materials and steel materials. Is being widely used in.
例えば、特許文献１には、第１の金属材料（鋼など）と、第１の金属材料とは種類の異なる第２の金属材料（アルミニウム合金など）との間に、これら二種類の金属材料とは異なる第３の金属材料（亜鉛など）を介在させ、超音波振動により、第１の金属材料及び第２の金属材料のうちの少なくとも一方の金属材料と第３の金属材料との間の界面に共晶溶融を生じさせて接合を行う方法が提案されている。
また、特許文献２には、超微細粒組織を有する２枚以上の鋼板の超音波接合において、鋼板の接合される面の少なくとも片側に亜鉛メッキを施し、所定の条件下で超音波接合することにより、亜鉛メッキを溶融させて鋼板に拡散接合する方法が提案されている。
さらに、特許文献３には、複数の被接合材が積層された被接合体の超音波接合において、超音波振動を発生する工具側に、複数の被接合材のうち相対的に低い降伏強度又は０．２％耐力を有する材料からなる被接合材を配置して超音波接合する方法が提案されている。
For example, Patent Document 1 states that between a first metal material (steel, etc.) and a second metal material (aluminum alloy, etc.) that is different from the first metal material, these two types of metal materials are used. A third metal material (such as zinc) different from the above is interposed, and ultrasonic vibration is applied between at least one of the first metal material and the second metal material and the third metal material. A method has been proposed in which eutectic melting is generated at the interface to perform bonding.
Further, Patent Document 2 states that in ultrasonic bonding of two or more steel sheets having an ultrafine grain structure, at least one side of the surface to which the steel sheets are bonded is galvanized and ultrasonically bonded under predetermined conditions. Has proposed a method of melting galvanizing and diffusing bonding to a steel sheet.
Further, Patent Document 3 states that in ultrasonic bonding of a bonded body in which a plurality of bonded materials are laminated, a relatively low yield strength of the plurality of bonded materials is provided on the tool side that generates ultrasonic vibration. A method has been proposed in which a material to be bonded made of a material having a 0.2% proof stress is arranged and ultrasonically bonded.
鋼板同士を接合した部品や製品などは、様々な分野において広く用いられているが、近年、接合部の特性低下や変形を抑制する必要性が高くなってきている。
しかしながら、特許文献１の技術は、異種金属間の接合を対象としており、鋼材同士の接合に適用することができない。
また、特許文献２に記載の技術は、鋼板同士の接合に関するものであるものの、鋼板に亜鉛メッキを施すことが必須である。
さらに、特許文献３に記載の技術は、接合する鋼板の降伏強度又は０．２％耐力が異なることを前提としており、接合する鋼板の降伏強度又は０．２％耐力が同一である場合には鋼板同士の接合が難しいと考えられる。
Parts and products in which steel sheets are joined to each other are widely used in various fields, but in recent years, there has been an increasing need to suppress deterioration and deformation of joints.
However, the technique of Patent Document 1 is intended for joining dissimilar metals, and cannot be applied to joining steel materials.
Further, although the technique described in Patent Document 2 relates to joining steel sheets to each other, it is essential to galvanize the steel sheets.
Further, the technique described in Patent Document 3 is based on the premise that the yield strength or 0.2% proof stress of the steel sheets to be joined is different, and when the yield strength or 0.2% proof stress of the steel sheets to be joined is the same. It is considered difficult to join the steel plates.
本発明は、上記のような課題を解決するためになされたものであり、超音波接合によって同種の鋼板同士を接合しても十分な接合強度を得ることが可能な超音波接合用鋼板、超音波接合用高強度鋼板及び超音波接合方法を提供することを目的とする。 The present invention has been made to solve the above problems, and is an ultrasonic bonding steel plate, which can obtain sufficient bonding strength even when the same type of steel sheets are bonded to each other by ultrasonic bonding. It is an object of the present invention to provide a high-strength steel plate for ultrasonic bonding and an ultrasonic bonding method.
本発明者らは、上記の課題を解決すべく鋭意研究を行った結果、鋼板の金属組織中のフェライト面積率及び０．２％耐力が、超音波接合による接合強度と密接に関係しているという知見に基づき、金属組織中のフェライト面積率及び０．２％耐力を特定の範囲に制御することにより、超音波接合による鋼板同士の接合強度を向上させ得ることを見出し、本発明を完成するに至った。 As a result of diligent research to solve the above problems, the present inventors have found that the ferrite area ratio and 0.2% proof stress in the metal structure of a steel plate are closely related to the bonding strength by ultrasonic bonding. Based on this finding, it was found that the bonding strength between steel sheets by ultrasonic bonding can be improved by controlling the ferrite area ratio and 0.2% proof stress in the metal structure within a specific range, and complete the present invention. It came to.
すなわち、本発明は、金属組織中のフェライト面積率が１０％以上であるとともに、０．２％耐力が５００Ｎ／ｍｍ2以下である超音波接合用鋼板である。
また、本発明は、前記超音波接合用鋼板に冷延率：１０％以上の冷間圧延が施された超音波接合用高強度鋼板である。
さらに、本発明は、２つ以上の鋼板を超音波接合する方法であって、前記鋼板の少なくとも１つが、前記超音波接合用鋼板又は前記超音波接合用高強度鋼板であり、前記超音波接合が、周波数：２０〜４０ｋＨｚ、出力：８００Ｗ以上、加圧時間：０．２秒以上、加圧力：５００〜２０００Ｎの条件で行われる超音波接合方法である。
That is, the present invention is a steel sheet for ultrasonic bonding in which the ferrite area ratio in the metal structure is 10% or more and the 0.2% proof stress is 500 N / mm 2 or less.
Further, the present invention is a high-strength steel sheet for ultrasonic bonding in which the steel sheet for ultrasonic bonding is cold-rolled with a cold rolling ratio of 10% or more.
Further, the present invention is a method of ultrasonically bonding two or more steel plates, wherein at least one of the steel plates is the ultrasonic bonding steel plate or the ultrasonic bonding high strength steel plate, and the ultrasonic bonding is performed. However, this is an ultrasonic bonding method performed under the conditions of frequency: 20 to 40 kHz, output: 800 W or more, pressurizing time: 0.2 seconds or more, and pressing force: 500 to 2000 N.
本発明によれば、超音波接合によって同種の鋼板同士を接合しても十分な接合強度を得ることが可能な超音波接合用鋼板、超音波接合用高強度鋼板及び超音波接合方法を提供することができる。 According to the present invention, there are provided a steel plate for ultrasonic bonding, a high-strength steel sheet for ultrasonic bonding, and an ultrasonic bonding method capable of obtaining sufficient bonding strength even if steel sheets of the same type are bonded to each other by ultrasonic bonding. be able to.
以下、本発明の実施形態について具体的に説明する。本発明は以下の実施形態に限定されるものではなく、本発明の趣旨を逸脱しない範囲で、当業者の通常の知識に基づいて、以下の実施形態に対し変更、改良などが適宜加えられたものも本発明の範囲に入ることが理解されるべきである。 Hereinafter, embodiments of the present invention will be specifically described. The present invention is not limited to the following embodiments, and changes, improvements, etc. have been appropriately added to the following embodiments based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. It should be understood that things also fall within the scope of the present invention.
（実施形態１）
本発明の実施形態１に係る超音波接合用鋼板（以下、「鋼板」と略すことがある）は、金属組織中のフェライト面積率が１０％以上であるとともに、０．２％耐力が５００Ｎ／ｍｍ2以下である。
以下、本発明の実施形態１に係る超音波接合用鋼板の特徴について詳細に説明する。
(Embodiment 1)
The ultrasonic bonding steel sheet according to the first embodiment of the present invention (hereinafter, may be abbreviated as "steel sheet") has a ferrite area ratio in a metal structure of 10% or more and a 0.2% strength of 500 N /. It is mm 2 or less.
Hereinafter, the features of the ultrasonic bonding steel sheet according to the first embodiment of the present invention will be described in detail.
＜金属組織＞
鋼板の金属組織におけるフェライト組織は、超音波接合による接合強度に影響を与える因子の１つであり、金属組織中のフェライト面積率が高いほど、超音波接合による接合強度が向上する。超音波接合によって良好な接合強度を得る観点からは、金属組織中のフェライト面積率を１０％以上、好ましくは６０％以上、さらに好ましくは９０％以上に制御する。なお、金属組織中のフェライト面積率の上限は、特に限定されず、１００％であってもよい。
ここで、本明細書において「金属組織中のフェライト面積率」とは、鋼板の圧延方向に平行な断面を光学顕微鏡で観察し、画像解析して算出されたフェライト面積率のことを意味する。
<Metal structure>
The ferrite structure in the metal structure of a steel plate is one of the factors that affect the bonding strength by ultrasonic bonding, and the higher the ferrite area ratio in the metal structure, the higher the bonding strength by ultrasonic bonding. From the viewpoint of obtaining good bonding strength by ultrasonic bonding, the ferrite area ratio in the metal structure is controlled to 10% or more, preferably 60% or more, and more preferably 90% or more. The upper limit of the ferrite area ratio in the metal structure is not particularly limited and may be 100%.
Here, in the present specification, the "ferrite area ratio in the metal structure" means the ferrite area ratio calculated by observing a cross section parallel to the rolling direction of the steel sheet with an optical microscope and performing image analysis.
＜０．２％耐力＞
鋼板の０．２％耐力も、超音波接合による接合強度に影響を与える因子の１つであり、０．２％耐力が低いほど、超音波接合による接合強度が向上する。超音波接合によって良好な接合強度を得る観点からは、０．２％耐力を５００Ｎ／ｍｍ2以下、好ましくは３２０Ｎ／ｍｍ2以下に制御する。なお、０．２％耐力の下限は、特に限定されないが、一般に１００Ｎ／ｍｍ2である。
ここで、本明細書において「０．２％耐力」とは、ＪＩＳ Ｚ２２４１：２０１１に準拠して測定される０．２％耐力を意味する。
<0.2% proof stress>
The 0.2% proof stress of the steel sheet is also one of the factors that affect the bonding strength by ultrasonic bonding, and the lower the 0.2% proof stress, the better the bonding strength by ultrasonic bonding. From the viewpoint of obtaining good bonding strength by ultrasonic bonding, the 0.2% proof stress is controlled to 500 N / mm 2 or less, preferably 320 N / mm 2 or less. The lower limit of the 0.2% proof stress is not particularly limited, but is generally 100 N / mm 2 .
Here, "0.2% proof stress" as used herein means 0.2% proof stress measured in accordance with JIS Z2241: 2011.
＜組成＞
鋼板の組成は、特に限定されないが、Ｃ：０．６５質量％以下、Ｓｉ：０．５０質量％以下、Ｍｎ：１．００質量％以下、Ｐ：０．０５質量％以下、Ｓ：０．０２質量％以下、Ｔｉ：０．１０質量％以下、Ｂ：０．０１質量％以下、Ａｌ：０．０００５〜０．１質量％を含有し、残部がＦｅ及び不可避的不純物からなることが好ましい。また、鋼板は、必要に応じて、Ｎｂ：０．１０質量％以下及びＶ：０．１０質量％以下から選択される１種以上をさらに含有することができる。
ここで、本明細書において「不可避的不純物」とは、Ｏ、Ｎなどの除去することが難しい成分のことを意味する。不可避的不純物は、原料を溶製する段階で不可避的に混入する。
以下、鋼板の組成について詳細に説明する。
<Composition>
The composition of the steel plate is not particularly limited, but C: 0.65% by mass or less, Si: 0.50% by mass or less, Mn: 1.00% by mass or less, P: 0.05% by mass or less, S: 0. It preferably contains 02% by mass or less, Ti: 0.10% by mass or less, B: 0.01% by mass or less, Al: 0.0005 to 0.1% by mass, and the balance is Fe and unavoidable impurities. .. Further, the steel sheet can further contain one or more selected from Nb: 0.10% by mass or less and V: 0.10% by mass or less, if necessary.
Here, the term "unavoidable impurities" as used herein means components such as O and N that are difficult to remove. Inevitable impurities are inevitably mixed in at the stage of melting the raw material.
Hereinafter, the composition of the steel sheet will be described in detail.
（Ｃ：０．６５質量％以下）
Ｃは、セメンタイトなどの炭化物を形成してフェライト組織中に析出し、フェライト面積率を低下させるとともに０．２％耐力を上昇させる。そのため、Ｃは、超音波接合による接合強度を低下させる原因になる元素といえる。特に、Ｃの含有量が０．６５質量％を超えると、金属組織中のフェライト面積率が１０％未満となり易い。したがって、Ｃの含有量は、好ましくは０．６５質量％以下、より好ましくは０．１０質量％以下に制御する。このような範囲にＣの含有量を制御することにより、金属組織中のフェライト面積率及び０．２％耐力を上記の範囲に制御し易くなる。
なお、Ｃの含有量は低いほど好ましいため、その下限は特に限定されない。
(C: 0.65% by mass or less)
C forms carbides such as cementite and precipitates in the ferrite structure, which lowers the ferrite area ratio and increases the proof stress by 0.2%. Therefore, C can be said to be an element that causes a decrease in bonding strength due to ultrasonic bonding. In particular, when the C content exceeds 0.65% by mass, the ferrite area ratio in the metal structure tends to be less than 10%. Therefore, the content of C is preferably controlled to 0.65% by mass or less, more preferably 0.10% by mass or less. By controlling the C content in such a range, it becomes easy to control the ferrite area ratio and the 0.2% proof stress in the metal structure within the above range.
Since the lower the C content is, the more preferable it is, the lower limit thereof is not particularly limited.
（Ｓｉ：０．５０質量％以下）
Ｓｉは、フェライト変態を促進させるのに有効な元素であるが、固溶強化によって０．２％耐力を上昇させる。そのため、Ｓｉも、超音波接合による接合強度を低下させる原因になる元素といえる。したがって、Ｓｉの含有量は、好ましくは０．５０質量％以下、より好ましくは０．１０質量％以下に制御する。このような範囲にＳｉの含有量を制御することにより、０．２％耐力の上昇を許容可能な範囲に抑えつつ、金属組織中のフェライト面積率を高めることができる。
なお、Ｓｉの含有量は低いほど好ましいため、その下限は特に限定されない。
(Si: 0.50% by mass or less)
Si is an element effective for promoting ferrite transformation, but the yield strength is increased by 0.2% by solid solution strengthening. Therefore, Si can also be said to be an element that causes a decrease in bonding strength due to ultrasonic bonding. Therefore, the Si content is preferably controlled to 0.50% by mass or less, more preferably 0.10% by mass or less. By controlling the Si content within such a range, it is possible to increase the ferrite area ratio in the metal structure while suppressing the increase in 0.2% proof stress within an acceptable range.
Since the lower the Si content is, the more preferable it is, the lower limit thereof is not particularly limited.
（Ｍｎ：１．００質量％以下）
Ｍｎは、Ｓｉと同様に、フェライト変態を促進させるのに有効な元素であるが、固溶強化によって０．２％耐力を上昇させる。そのため、Ｍｎも、超音波接合による接合強度を低下させる原因になる元素といえる。したがって、Ｍｎの含有量は、好ましくは１．００質量％以下、より好ましくは０．５０質量％以下に制御する。このような範囲にＭｎの含有量を制御することにより、０．２％耐力の上昇を許容可能な範囲に抑えつつ、金属組織中のフェライト面積率を高めることができる。
なお、Ｍｎの含有量は低いほど好ましいため、その下限は特に限定されない。
(Mn: 1.00% by mass or less)
Mn, like Si, is an element effective in promoting ferrite transformation, but the proof stress is increased by 0.2% by solid solution strengthening. Therefore, Mn can also be said to be an element that causes a decrease in bonding strength due to ultrasonic bonding. Therefore, the Mn content is preferably controlled to 1.00% by mass or less, more preferably 0.50% by mass or less. By controlling the Mn content within such a range, it is possible to increase the ferrite area ratio in the metal structure while suppressing the increase in 0.2% proof stress within an acceptable range.
Since the lower the Mn content is, the more preferable it is, the lower limit thereof is not particularly limited.
（Ｐ：０．０５質量％以下）
Ｐは、固溶強化によって０．２％耐力を上昇させる。そのため、Ｐも、超音波接合による接合強度を低下させる原因になる元素といえる。したがって、Ｐの含有量は、好ましくは０．０５質量％以下、より好ましくは０．０２質量％以下に制御する。このような範囲にＰの含有量を制御することにより、０．２％耐力の上昇を許容可能な範囲に抑えることができる。
なお、Ｐの含有量は低いほど好ましいため、その下限は特に限定されない。
(P: 0.05% by mass or less)
P increases the yield strength by 0.2% by solid solution strengthening. Therefore, it can be said that P is also an element that causes a decrease in bonding strength by ultrasonic bonding. Therefore, the content of P is preferably controlled to 0.05% by mass or less, more preferably 0.02% by mass or less. By controlling the content of P in such a range, an increase in 0.2% proof stress can be suppressed within an acceptable range.
Since the lower the P content is, the more preferable it is, the lower limit thereof is not particularly limited.
（Ｓ：０．０２質量％以下）
Ｓは、Ｍｎと硫化物を形成し、曲げ加工性を始めとする局部延性を劣化させる。そのため、Ｓは、局部延性の観点から、極力低減すべき元素である。したがって、Ｓの含有量は、好ましくは０．０２質量％以下、より好ましくは０．０１質量％以下、さらに好ましくは０．００５質量％以下に制御する。このような範囲にＳの含有量を制御することにより、局部延性の劣化を許容可能な範囲に抑えることができる。
なお、Ｓの含有量は低いほど好ましいため、その下限は特に限定されない。
(S: 0.02% by mass or less)
S forms a sulfide with Mn and deteriorates local ductility including bending workability. Therefore, S is an element that should be reduced as much as possible from the viewpoint of local ductility. Therefore, the content of S is preferably controlled to 0.02% by mass or less, more preferably 0.01% by mass or less, and further preferably 0.005% by mass or less. By controlling the S content within such a range, the deterioration of local ductility can be suppressed within an acceptable range.
Since the lower the S content is, the more preferable it is, the lower limit thereof is not particularly limited.
（Ｔｉ：０．１０質量％以下）
Ｔｉは、Ｃと結合して微細なＴｉの炭化物として析出するため、セメンタイトの析出抑制に有効な元素である。しかし、微細な炭化物は０．２％耐力を上昇させるため、超音波接合による接合強度を低下させる原因になる。したがって、Ｔｉの含有量は、好ましくは０．１０質量％以下、より好ましくは０．０８質量％以下に制御する。このような範囲にＴｉの含有量を制御することにより、０．２％耐力の上昇を許容可能な範囲に抑えつつ、金属組織中のフェライト面積率を高めることができる。
なお、Ｔｉの含有量は低いほど好ましいため、その下限は特に限定されない。
(Ti: 0.10% by mass or less)
Ti is an element effective in suppressing the precipitation of cementite because it binds to C and precipitates as a fine carbide of Ti. However, since fine carbides increase the yield strength by 0.2%, they cause a decrease in bonding strength by ultrasonic bonding. Therefore, the Ti content is preferably controlled to 0.10% by mass or less, more preferably 0.08% by mass or less. By controlling the Ti content within such a range, it is possible to increase the ferrite area ratio in the metal structure while suppressing the increase in 0.2% proof stress within an acceptable range.
Since the lower the Ti content, the more preferable it is, the lower limit thereof is not particularly limited.
（Ｂ：０．０１質量％以下）
Ｂは、結晶粒界に偏析して原子間結合力を高めるため、低温靭性の改善に有効な元素である。しかし、Ｂは、フェライト結晶粒径を微細化し、０．２％耐力を上昇させるため、超音波接合による接合強度を低下させる原因になる。したがって、Ｂの含有量は、好ましくは０．０１質量％以下、より好ましくは０．００５質量％以下に制御する。このような範囲にＢの含有量を制御することにより、０．２％耐力の上昇を許容可能な範囲に抑えつつ、低温靭性を向上させることができる。
なお、Ｂの含有量は低いほど好ましいため、その下限は特に限定されない。
(B: 0.01% by mass or less)
B is an element effective for improving low temperature toughness because it segregates at the grain boundaries and enhances the atomic bond force. However, B makes the ferrite crystal grain size finer and increases the proof stress by 0.2%, which causes a decrease in bonding strength by ultrasonic bonding. Therefore, the content of B is preferably controlled to 0.01% by mass or less, more preferably 0.005% by mass or less. By controlling the content of B in such a range, it is possible to improve the low temperature toughness while suppressing the increase in 0.2% proof stress within an acceptable range.
Since the lower the B content is, the more preferable it is, the lower limit thereof is not particularly limited.
（Ａｌ：０．０００５〜０．１質量％）
Ａｌは、製鋼時に脱酸材として添加される元素である。その効果を十分に得るためには、Ａｌの含有量を好ましくは０．０００５質量％以上、より好ましくは０．００１０質量％以上に制御する。一方、Ａｌの含有量が多くなると、その効果は飽和するとともにかえって製造コストの上昇を招くため、Ａｌの含有量を好ましくは０．１質量％以下、より好ましくは０．０５質量％以下に制御する。
(Al: 0.0005 to 0.1% by mass)
Al is an element added as a deoxidizing material during steelmaking. In order to obtain the effect sufficiently, the Al content is preferably controlled to 0.0005% by mass or more, more preferably 0.0010% by mass or more. On the other hand, when the Al content is increased, the effect is saturated and the production cost is increased. Therefore, the Al content is preferably controlled to 0.1% by mass or less, more preferably 0.05% by mass or less. To do.
（Ｎｂ：０．１０質量％以下、Ｖ：０．１０質量％以下の１種以上）
ＮｂやＶも、Ｔｉと同様に、Ｃと結合して微細なＴｉの炭化物として析出するため、セメンタイトの析出抑制に有効な元素である。しかし、微細な炭化物は０．２％耐力を上昇させるため、超音波接合による接合強度を低下させる原因になる。したがって、Ｎｂ及びＶの含有量はそれぞれ、好ましくは０．１０質量％以下、より好ましくは０．０８質量％以下に制御する。
なお、Ｎｂ及びＶの含有量は低いほど好ましいため、その下限は特に限定されない。
(Nb: 0.10% by mass or less, V: one or more types of 0.10% by mass or less)
Like Ti, Nb and V also combine with C and precipitate as fine carbides of Ti, and are therefore effective elements for suppressing the precipitation of cementite. However, since fine carbides increase the yield strength by 0.2%, they cause a decrease in bonding strength by ultrasonic bonding. Therefore, the contents of Nb and V are preferably controlled to 0.10% by mass or less, more preferably 0.08% by mass or less, respectively.
Since the lower the content of Nb and V is, the more preferable it is, the lower limit thereof is not particularly limited.
＜厚さ＞
鋼板の厚さは、特に限定されないが、好ましくは３．０ｍｍ未満、より好ましくは０．１〜２．０ｍｍ、さらに好ましくは０．５〜１．５ｍｍである。
<Thickness>
The thickness of the steel sheet is not particularly limited, but is preferably less than 3.0 mm, more preferably 0.1 to 2.0 mm, and even more preferably 0.5 to 1.5 mm.
＜製造方法＞
本発明の実施形態１に係る鋼板は、当該技術分野において公知の方法（薄鋼板の製造方法）に準じて製造することができる。具体的には、上記の組成を有する鋼を溶製した後、連続鋳造、熱間圧延、冷間圧延、連続焼鈍及び調質圧延を順次行うことにより、本発明の実施形態１に係る鋼板を製造することができる。また、必要に応じて、酸洗などの公知の処理を適切な段階で行ってもよい。
<Manufacturing method>
The steel sheet according to the first embodiment of the present invention can be manufactured according to a method known in the art (a method for manufacturing a thin steel sheet). Specifically, the steel sheet according to the first embodiment of the present invention is obtained by sequentially performing continuous casting, hot rolling, cold rolling, continuous annealing, and temper rolling after melting a steel having the above composition. Can be manufactured. Further, if necessary, a known treatment such as pickling may be performed at an appropriate stage.
（実施形態２）
本発明の実施形態２に係る超音波接合用高強度鋼板（以下、「高強度鋼板」と略すことがある）は、本発明の実施形態１に係る超音波接合用鋼板に冷延率：１０％以上の冷間圧延が施されたものである。このような冷延率で冷間圧延を施すことにより、本発明の実施形態１に係る超音波接合用鋼板の効果（超音波接合による接合強度の向上効果）に加えて、それ自体の強度を高めることができる。冷延率が１０％未満であると、鋼板の強度を十分に高めることができない。冷延率は、高くなるほど、超音波接合による接合強度が低下する傾向にあるものの、固溶強化や変態強化などの他の強化手段によって高強度化した場合に比べて、超音波接合による接合強度は低下し難い。これは、金属組織中のフェライト面積率が高いことなどに起因すると思われるが、詳細は明らかでない。
なお、冷延率の上限は、特に限定されないが、冷延率が高すぎると、板厚が小さくなり過ぎて用途が限定される。そのため、冷延率の上限は８０％とすることが好ましい。
(Embodiment 2)
The high-strength steel sheet for ultrasonic bonding according to the second embodiment of the present invention (hereinafter, may be abbreviated as "high-strength steel sheet") is the steel sheet for ultrasonic bonding according to the first embodiment of the present invention with a cold rolling ratio of 10: It is cold-rolled by% or more. By performing cold rolling at such a cold rolling ratio, in addition to the effect of the steel sheet for ultrasonic bonding according to the first embodiment of the present invention (the effect of improving the bonding strength by ultrasonic bonding), the strength of itself can be increased. Can be enhanced. If the cold rolling ratio is less than 10%, the strength of the steel sheet cannot be sufficiently increased. The higher the cold rolling ratio, the lower the bonding strength by ultrasonic bonding tends to be, but the bonding strength by ultrasonic bonding is higher than that when the strength is increased by other strengthening means such as solid solution strengthening and transformation strengthening. Is hard to drop. This is thought to be due to the high ferrite area ratio in the metal structure, but the details are not clear.
The upper limit of the cold rolling ratio is not particularly limited, but if the cold rolling ratio is too high, the plate thickness becomes too small and the application is limited. Therefore, the upper limit of the cold rolling ratio is preferably 80%.
高強度鋼板の厚さは、特に限定されないが、好ましくは２．７ｍｍ未満、より好ましくは０．０２〜１．８ｍｍ、さらに好ましくは０．１〜１．３５ｍｍである。 The thickness of the high-strength steel sheet is not particularly limited, but is preferably less than 2.7 mm, more preferably 0.02 to 1.8 mm, and further preferably 0.1 to 1.35 mm.
（実施形態３）
本発明の実施形態３に係る超音波接合方法は、２つ以上の鋼板を超音波接合するものである。
本発明の実施形態３に係る超音波接合方法では、２つ以上の鋼板のうちの少なくとも１つが、本発明の実施形態１に係る鋼板、又は本発明の実施形態２に係る高強度鋼板である。例えば、２つの鋼板のうちの１つが本発明の実施形態１に係る鋼板又は本発明の実施形態２に係る高強度鋼板であってよく、２つが本発明の実施形態１に係る鋼板又は本発明の実施形態２に係る高強度鋼板であってもよい。また、２つの鋼板のうちの１つが本発明の実施形態１に係る鋼板、もう１つが本発明の実施形態２に係る高強度鋼板であってもよい。
(Embodiment 3)
The ultrasonic bonding method according to the third embodiment of the present invention is to ultrasonically bond two or more steel plates.
In the ultrasonic bonding method according to the third embodiment of the present invention, at least one of the two or more steel plates is the steel plate according to the first embodiment of the present invention or the high-strength steel plate according to the second embodiment of the present invention. .. For example, one of the two steel sheets may be the steel sheet according to the first embodiment of the present invention or the high-strength steel sheet according to the second embodiment of the present invention, and two may be the steel sheet according to the first embodiment of the present invention or the present invention. The high-strength steel sheet according to the second embodiment of the above may be used. Further, one of the two steel plates may be the steel plate according to the first embodiment of the present invention, and the other may be the high-strength steel plate according to the second embodiment of the present invention.
超音波接合は、ホーンと、ホーンに対向して配置されたアンビルとを備える超音波接合装置を用い、ホーンとアンビルとの間に２つ以上の鋼板の積層体を配置して行うことができる。ホーンには超音波発振器が接続されており、超音波発振器からの信号をコンバーター及びブースターで増幅することにより、ホーンが超音波振動される。ホーンの先端を鋼板に押し当てて加圧しながら超音波振動させることにより、接合界面に摩擦が生じ、表面の吸着汚れや酸化皮膜などを除去することができる。このようにして生じた鋼板の新生面同士を圧着することで鋼板同士を接合することができる。さらに一定時間加圧を続けると、接合界面近傍に大きな塑性流動が生じて接合面積が増大するため、鋼板間の接合強度を高めることができる。 Ultrasonic bonding can be performed by using an ultrasonic bonding device including a horn and an anvil arranged so as to face the horn, and arranging a laminate of two or more steel plates between the horn and the anvil. .. An ultrasonic oscillator is connected to the horn, and the horn is ultrasonically vibrated by amplifying the signal from the ultrasonic oscillator with a converter and a booster. By pressing the tip of the horn against the steel plate and vibrating it ultrasonically while applying pressure, friction is generated at the bonding interface, and adsorption stains and oxide film on the surface can be removed. The steel plates can be joined to each other by crimping the new surfaces of the steel plates thus generated. If the pressurization is continued for a certain period of time, a large plastic flow is generated near the bonding interface and the bonding area is increased, so that the bonding strength between the steel sheets can be increased.
ホーンは、一般に、被接合材と接触する先端部に超硬合金製のチップを有するが、特に鋼板を被接合材として用いる場合、超硬合金製のチップでは靭性が十分でなく早期に破損してしまうことがある。したがって、鋼板と接するホーンの先端部（チップ）が高速度工具鋼から形成されていることが好ましく、先端部（チップ）がホーンと高速度工具鋼で一体形成されていることがより好ましい。このような構成とすることにより、チップが早期に破損することを抑制することができる。
ここで、本明細書において「高速度工具鋼」とは、ＪＩＳ Ｚ４４０３：２０１５に規定される高速度工具鋼を意味する。
The horn generally has a cemented carbide tip at the tip that comes into contact with the material to be joined, but especially when a steel plate is used as the material to be joined, the tip made of cemented carbide is not sufficiently tough and breaks early. It may end up. Therefore, it is preferable that the tip portion (tip) of the horn in contact with the steel plate is formed of high-speed tool steel, and it is more preferable that the tip portion (tip) is integrally formed of the horn and high-speed tool steel. With such a configuration, it is possible to prevent the chip from being damaged at an early stage.
Here, the term "high-speed tool steel" as used herein means high-speed tool steel defined in JIS Z4403: 2015.
また、ホーンの先端部の表面には、硬質膜が設けられていることが好ましい。硬質膜の種類は、特に限定されないが、ＴｉＮ、ＣｒＮ又はＤＬＣ（ダイヤモンドライクカーボン）コーティングが施されていることが好ましい。このような硬質膜を設けることにより、ホーンの先端部の磨耗を抑制することができるため、ホーンの寿命を延ばすことが可能となる。 Further, it is preferable that a hard film is provided on the surface of the tip portion of the horn. The type of the hard film is not particularly limited, but it is preferable that a TiN, CrN or DLC (diamond-like carbon) coating is applied. By providing such a hard film, it is possible to suppress the wear of the tip portion of the horn, so that the life of the horn can be extended.
超音波接合は、以下の条件で行われる。
＜周波数：２０〜４０ｋＨｚ＞
周波数は、２０ｋＨｚ以上でないと十分な接合強度が得られない。一方、４０ｋＨｚを超える周波数では、十分な出力（振幅）で振動させることが困難となり、かえって十分な接合強度が得られなくなる。したがって、周波数は２０〜４０ｋＨｚの範囲に制御する。
Ultrasonic bonding is performed under the following conditions.
<Frequency: 20-40kHz>
Sufficient junction strength cannot be obtained unless the frequency is 20 kHz or higher. On the other hand, at a frequency exceeding 40 kHz, it becomes difficult to vibrate with a sufficient output (amplitude), and on the contrary, a sufficient junction strength cannot be obtained. Therefore, the frequency is controlled in the range of 20 to 40 kHz.
＜出力：８００Ｗ以上＞
出力は、８００Ｗ以上でないと十分な接合強度が得られない。一方、出力の上限は、特に限定されないが、出力が大きすぎるとホーン及び鋼板表面の損傷を招く恐れがあるため、４０００Ｗ以下とすることが好ましい。
<Output: 800W or more>
Sufficient bonding strength cannot be obtained unless the output is 800 W or more. On the other hand, the upper limit of the output is not particularly limited, but it is preferably 4000 W or less because if the output is too large, the horn and the surface of the steel plate may be damaged.
＜加圧時間：０．２秒以上＞
加圧時間は、０．２秒以上でないと、接合面積が小さくなるため十分な接合強度が得られない。そのため、加圧時間は０．２秒以上に制御する。加圧時間の上限は、特に限定されないが、時間が長すぎると鋼板やホーン先端で大きな温度上昇を招き、ホーンや鋼板表面の損傷を招くため、５秒以下とすることが好ましい。
<Pressurization time: 0.2 seconds or more>
If the pressurizing time is not 0.2 seconds or more, the bonding area becomes small and sufficient bonding strength cannot be obtained. Therefore, the pressurization time is controlled to 0.2 seconds or more. The upper limit of the pressurizing time is not particularly limited, but if the time is too long, a large temperature rise is caused at the tip of the steel plate or the horn, which causes damage to the horn or the surface of the steel plate. Therefore, it is preferably 5 seconds or less.
＜加圧力：５００〜２０００Ｎ＞
加圧力は、５００Ｎ以上でないと、接合面積が小さくなるため十分な接合強度が得られない。一方、加圧力が高すぎると、鋼板表面やホーン先端部が損傷する。したがって、加圧力は５００〜２０００Ｎの範囲に制御する。
<Pressure: 500-2000N>
If the pressing force is not 500 N or more, the joint area becomes small and sufficient joint strength cannot be obtained. On the other hand, if the pressing force is too high, the surface of the steel plate and the tip of the horn will be damaged. Therefore, the pressing force is controlled in the range of 500 to 2000 N.
以下に、実施例を挙げて本発明の内容を詳細に説明するが、本発明はこれらに限定して解釈されるものではない。 Hereinafter, the contents of the present invention will be described in detail with reference to examples, but the present invention is not construed as being limited thereto.
（実施例１）
表１に示す組成（残部はＦｅ及び不可避的不純物である）を有する各鋼を通常の薄鋼板の製造工程に準じて連続鋳造、熱間圧延、冷間圧延、連続焼鈍及び調質圧延を順次行うことによって、厚さ１．０ｍｍの冷延鋼板（超音波接合用鋼板）を得た。
(Example 1)
Each steel having the composition shown in Table 1 (the balance is Fe and unavoidable impurities) is continuously cast, hot rolled, cold rolled, continuously annealed and tempered according to a normal thin steel sheet manufacturing process. By doing so, a cold-rolled steel sheet (steel sheet for ultrasonic bonding) having a thickness of 1.0 mm was obtained.
得られた冷延鋼板について、以下の評価を行った。
まず、上記の方法に従って金属組織中のフェライト面積率及び０．２％耐力を評価した。０．２％耐力はＪＩＳ Ｚ２２４１：２０１１に準拠して測定を行い、試験片には、引張方向が圧延方向と平行な方向となるように採取した５号試験片を用いた。
次に、各冷延鋼板から幅２５ｍｍ、長さ１００ｍｍの短冊状の試験片を切り出した後、超音波接合装置を用いて超音波接合を行って接合強度を評価した。試験片は、長さ方向が圧延方向と一致するようにした。また、超音波接合は、同じ組成の冷延鋼板の試験片２つを用い、図１に示すように、２つの試験片１０の先端部が３０ｍｍ重なるように積層させた。そして、この積層部の上側の接触部２０にホーンの先端を接触させるとともに下側をアンビルによって支持した後、周波数：２０ｋＨｚ、出力：３０００Ｗ（振幅：約４０μｍ）、加圧時間：１．０秒、加圧力：１５００Ｎの条件下で超音波接合を行った。ホーンは高速度工具鋼のＳＫＨ５１にて作製し、先端形状は３．５ｍｍ×１５ｍｍの範囲に２列×７個のローレットパターンを有する形状とした。
The obtained cold-rolled steel sheet was evaluated as follows.
First, the ferrite area ratio and 0.2% proof stress in the metal structure were evaluated according to the above method. The 0.2% proof stress was measured in accordance with JIS Z2241: 2011, and as the test piece, a No. 5 test piece collected so that the tensile direction was parallel to the rolling direction was used.
Next, a strip-shaped test piece having a width of 25 mm and a length of 100 mm was cut out from each cold-rolled steel sheet, and then ultrasonically bonded using an ultrasonic bonding device to evaluate the bonding strength. The test piece was made so that the length direction coincided with the rolling direction. For ultrasonic bonding, two cold-rolled steel sheet test pieces having the same composition were used, and as shown in FIG. 1, the two test pieces 10 were laminated so that the tips of the two test pieces 10 overlapped by 30 mm. Then, after the tip of the horn is brought into contact with the contact portion 20 on the upper side of the laminated portion and the lower side is supported by anvil, the frequency: 20 kHz, the output: 3000 W (amplitude: about 40 μm), and the pressurizing time: 1.0 second. , Ultrasonic bonding was performed under the condition of pressing force: 1500N. The horn was made of high-speed tool steel SKH51, and the tip shape had a shape having two rows x 7 knurled patterns in a range of 3.5 mm x 15 mm.
上記のようにして超音波接合された試験片についてＪＩＳ Ｚ２２４１：２０１１に準拠して、せん断引張試験を行った。せん断引張試験は、引張試験機を用い、引張速度５ｍｍ／分の条件で行い、最大強度（Ｎ）を測定した。また、下記の式に基づいて、最大応力も算出した。
最大応力（Ｎ／ｍｍ2）＝最大強度（Ｎ）／接合面積（ｍｍ2）
上記の式中、接合面積は、３．５ｍｍ×１５ｍｍとした。
上記の各結果を表２に示す。また、冷延鋼板の０．２％耐力と最大応力との関係を示すグラフを図２に示す。
Shear tensile tests were performed on the ultrasonically bonded test pieces as described above in accordance with JIS Z2241: 2011. The shear tensile test was carried out using a tensile tester under the condition of a tensile speed of 5 mm / min, and the maximum strength (N) was measured. The maximum stress was also calculated based on the following formula.
Maximum stress (N / mm 2 ) = maximum strength (N) / joint area (mm 2 )
In the above formula, the joint area was 3.5 mm × 15 mm.
Each of the above results is shown in Table 2. Further, FIG. 2 shows a graph showing the relationship between the 0.2% proof stress of the cold-rolled steel sheet and the maximum stress.
表２に示されるように、０．２％耐力及びフェライト面積率が所定の範囲内の試験Ｎｏ．１−２及び１−５〜１−１１（本発明例）の冷延鋼板は、０．２％耐力及びフェライト面積率が所定の範囲外の試験Ｎｏ．１−１、１−３及び１−４（比較例）の冷延鋼板に比べて、最大強度及び最大応力が高く、良好な接合強度を示した。また、図２に示されるように、０．２％耐力が小さくなるほど最大応力が大きくなる傾向にあり、特に０．２％耐力を３２０Ｎ／ｍｍ2以下とすることにより、最大応力が８０Ｎ／ｍｍ2以上の良好な接合強度を示した。 As shown in Table 2, Test Nos. With 0.2% proof stress and ferrite area ratio within predetermined ranges. The cold-rolled steel sheets 1-2 and 1-5 to 1-11 (example of the present invention) had a test No. 1 in which the 0.2% proof stress and the ferrite area ratio were out of the predetermined ranges. Compared with the cold-rolled steel sheets 1-1, 1-3 and 1-4 (comparative example), the maximum strength and the maximum stress were high, and good joint strength was exhibited. Further, as shown in FIG. 2, the maximum stress tends to increase as the 0.2% proof stress decreases. In particular, by setting the 0.2% proof stress to 320 N / mm 2 or less, the maximum stress tends to be 80 N / mm. It showed good bonding strength of 2 or more.
（実施例２）
表１に示す鋼種Ｎｏ．６及び８の組成（残部はＦｅ及び不可避的不純物である）を有する鋼を用い、実施例１と同様の工程を行うことにより、厚さ２．０ｍｍ、１．６ｍｍ、１．１２ｍｍ及び１．０５ｍｍの冷延鋼板（超音波接合用鋼板）を得た。厚さは、圧延率を変えることによって調整した。
次に、上記で得られた厚さ１．０５ｍｍ、１．１２ｍｍ及び１．６ｍｍの冷延鋼板は、厚さ１．０ｍｍ（冷延率はそれぞれ４．８％、１０．７％、３７．５％である）まで、厚さ２．０ｍｍの冷延鋼板は、厚さ１．０ｍｍ（冷延率５０％）及び０．４ｍｍ（冷延率８０％）まで冷間圧延をさらに施して高強度冷延鋼板（超音波接合用高強度鋼板）を得た。
(Example 2)
Steel type No. shown in Table 1. By using steel having the compositions of 6 and 8 (the balance is Fe and unavoidable impurities) and performing the same steps as in Example 1, the thicknesses of 2.0 mm, 1.6 mm, 1.12 mm and 1. A 05 mm cold-rolled steel sheet (steel for ultrasonic bonding) was obtained. The thickness was adjusted by changing the rolling ratio.
Next, the cold-rolled steel sheets having thicknesses of 1.05 mm, 1.12 mm and 1.6 mm obtained above were 1.0 mm thick (cold-rolled ratios were 4.8%, 10.7% and 37. Cold-rolled steel sheets with a thickness of 2.0 mm up to (5%) are further subjected to cold rolling to a thickness of 1.0 mm (cold rolling ratio 50%) and 0.4 mm (cold rolling ratio 80%) to increase the height. A high-strength cold-rolled steel sheet (high-strength steel sheet for ultrasonic bonding) was obtained.
上記で得られた冷延鋼板及び高強度冷延鋼板について、実施例１と同様の方法で、０．２％耐力を測定するとともに、冷延鋼板又は高強度冷延鋼板の同じ試験片２つを用いて超音波接合を行い、せん断引張試験を行った。その結果を表３に示す。
なお、鋼種Ｎｏ．６及び８を用いた実施例２の冷延鋼板及び高強度冷延鋼板のフェライト面積率は、鋼種Ｎｏ．６及び８を用いた実施例１の冷延鋼板のもの（表２の試験Ｎｏ．１−６及び１−８）とそれぞれ同じである。また、表３において、試験Ｎｏ．２−１、２−３、２−５、２−７、２−１０、２−１２、２−１４及び２−１６は冷延鋼板であり、それ以外は高強度冷延鋼板である。
また、実施例２における冷延鋼板及び高強度冷延鋼板の０．２％耐力と最大応力との関係を示すグラフを図３に示す。なお、図３では、比較のために、実施例１における冷延鋼板の０．２％耐力と最大応力との関係を示すグラフも合わせて示す。
With respect to the cold-rolled steel sheet and the high-strength cold-rolled steel sheet obtained above, the 0.2% strength was measured by the same method as in Example 1, and two same test pieces of the cold-rolled steel sheet or the high-strength cold-rolled steel sheet were used. The shear tension test was carried out by performing ultrasonic joining using. The results are shown in Table 3.
In addition, steel type No. The ferrite area ratio of the cold-rolled steel sheet and the high-strength cold-rolled steel sheet of Example 2 using 6 and 8 is the steel type No. It is the same as that of the cold-rolled steel sheet of Example 1 using 6 and 8 (Test Nos. 1-6 and 1-8 in Table 2, respectively). Further, in Table 3, the test No. 2-1, 2-3, 2-5, 2-7, 2-10, 2-12, 2-14 and 2-16 are cold-rolled steel sheets, and the others are high-strength cold-rolled steel sheets.
Further, FIG. 3 shows a graph showing the relationship between the 0.2% proof stress and the maximum stress of the cold-rolled steel sheet and the high-strength cold-rolled steel sheet in Example 2. In FIG. 3, for comparison, a graph showing the relationship between the 0.2% proof stress and the maximum stress of the cold-rolled steel sheet in Example 1 is also shown.
図３に示されるように、鋼種Ｎｏ．６及び８を用いて作製された冷延鋼板及び高強度冷延鋼板（本発明例）は、実施例１の試験Ｎｏ．１−１、１−３及び１−４（比較例）の冷延鋼板に比べて、最大強度及び最大応力が高く、良好な接合強度を示した。また、図３及び表３に示されるように、高強度冷延鋼板は、冷延鋼板に比べて、最大強度及び最大応力が若干低くなる傾向があるものの、その接合強度は十分なものであった。 As shown in FIG. 3, the steel grade No. The cold-rolled steel sheet and the high-strength cold-rolled steel sheet (example of the present invention) produced by using 6 and 8 are the test No. 1 of Example 1. Compared with the cold-rolled steel sheets 1-1, 1-3 and 1-4 (comparative example), the maximum strength and the maximum stress were high, and good joint strength was exhibited. Further, as shown in FIGS. 3 and 3, the high-strength cold-rolled steel sheet tends to have a slightly lower maximum strength and maximum stress than the cold-rolled steel sheet, but its joint strength is sufficient. It was.
（実施例３）
表１に示す鋼種Ｎｏ．２及び８の組成（残部はＦｅ及び不可避的不純物である）を有する鋼を用い、実施例１と同様の工程を行うことにより、厚さ１．０ｍｍの冷延鋼板（超音波接合用鋼板）を得た。
なお、鋼種Ｎｏ．２及び８を用いた実施例３の冷延鋼板の０．２％耐力及びフェライト面積率は、実施例１の冷延鋼板のもの（表２の試験Ｎｏ．１−２及び１−８の結果）とそれぞれ同じである。
上記で得られた冷延鋼板について、実施例１と同様にして冷延鋼板の同じ試験片２つを作製し、２つの試験片の先端部が３０ｍｍ重なるように積層させた後、周波数以外の条件を変えて超音波接合を行った。その後、実施例１と同様にしてせん断引張試験を行った。その結果を表４に示す。
(Example 3)
Steel type No. shown in Table 1. By using steel having the compositions of 2 and 8 (the balance is Fe and unavoidable impurities) and performing the same process as in Example 1, a cold-rolled steel sheet (steel sheet for ultrasonic bonding) having a thickness of 1.0 mm is used. Got
In addition, steel type No. The 0.2% proof stress and ferrite area ratio of the cold-rolled steel sheet of Example 3 using 2 and 8 are those of the cold-rolled steel sheet of Example 1 (results of Test Nos. 1-2 and 1-8 in Table 2). ) And each.
With respect to the cold-rolled steel sheet obtained above, two same test pieces of the cold-rolled steel sheet were prepared in the same manner as in Example 1, and after laminating so that the tips of the two test pieces overlapped by 30 mm, other than the frequency. Ultrasonic bonding was performed under different conditions. Then, a shear tensile test was performed in the same manner as in Example 1. The results are shown in Table 4.
表４に示されるように、超音波接合において出力を８００Ｗ以上、加圧時間を０．２秒以上、加圧力を５００〜２０００Ｎの範囲に制御したものは、当該範囲外のものに比べて最大強度及び最大応力が高く、良好な接合強度を示した。 As shown in Table 4, in ultrasonic bonding, the maximum output is 800 W or more, the pressurization time is 0.2 seconds or more, and the pressing force is controlled in the range of 500 to 2000 N, as compared with the one outside the range. The strength and maximum stress were high, showing good bonding strength.
（実施例４）
表１に示す鋼種Ｎｏ．８の組成（残部はＦｅ及び不可避的不純物である）を有する鋼を用い、実施例１と同様の工程を行うことにより、厚さ１．０ｍｍの冷延鋼板（超音波接合用鋼板）を得た。
なお、この冷延鋼板の０．２％耐力及びフェライト面積率は、実施例１の冷延鋼板のもの（表２の試験Ｎｏ．１−８の結果）と同じである。
(Example 4)
Steel type No. shown in Table 1. By using a steel having the composition of 8 (the balance is Fe and unavoidable impurities) and performing the same process as in Example 1, a cold-rolled steel sheet (steel sheet for ultrasonic bonding) having a thickness of 1.0 mm is obtained. It was.
The 0.2% proof stress and ferrite area ratio of this cold-rolled steel sheet are the same as those of the cold-rolled steel sheet of Example 1 (results of Test No. 1-8 in Table 2).
次に、超音波接合装置に用いるホーンとして、超硬合金製のチップを先端部にろう接したホーン（試験Ｎｏ．４−１）、先端部（チップ）が高速度工具鋼（ＳＫＨ５１）で一体形成されたホーン（試験Ｎｏ．４−２）、試験Ｎｏ．４−２のホーンの先端部にＤＬＣコーティング（厚さ１．５μｍ）を施したホーン（試験Ｎｏ．４−３）をそれぞれ準備した。なお、ホーンの先端形状は、３．５ｍｍ×１５ｍｍの範囲に２列×７個のローレットパターンを有する形状とした。
これらのホーンを超音波接合装置に組み込んだ後、実施例１と同様の条件で冷延鋼板の同じ試験片２つの超音波接合をホーン先端部に異常が発生するまで繰り返し行い、ホーン寿命を評価した。その結果を表５に示す。
Next, as horns used for ultrasonic bonding equipment, a horn (test No. 4-1) in which a cemented carbide tip is brazed to the tip, and the tip (tip) are integrated with high-speed tool steel (SKH51). The formed horn (test No. 4-2), test No. 4-2. Horns (Test No. 4-3) having a DLC coating (thickness 1.5 μm) applied to the tips of the horns of 4-2 were prepared. The tip shape of the horn was a shape having two rows x 7 knurled patterns in a range of 3.5 mm x 15 mm.
After incorporating these horns into an ultrasonic bonding device, ultrasonic bonding of two same test pieces of a cold-rolled steel sheet under the same conditions as in Example 1 is repeated until an abnormality occurs at the tip of the horn to evaluate the horn life. did. The results are shown in Table 5.
表５に示されるように、超硬合金製のチップを先端部にろう接したホーン（試験Ｎｏ．４−１）を用いた場合に比べて、先端部（チップ）が高速度工具鋼（ＳＫＨ５１）で一体形成されたホーン（試験Ｎｏ．４−２）を用いることで、ホーン寿命が著しく向上した。さらに、その先端部にＤＬＣコーティングを施したホーン（試験Ｎｏ．４−３）を用いることで、ホーン寿命が更に向上した。 As shown in Table 5, the tip (tip) is a high-speed tool steel (SKH51) as compared with the case where a horn (Test No. 4-1) in which a cemented carbide tip is brazed to the tip is used. ), The life of the horn was significantly improved by using the horn (Test No. 4-2). Further, by using a horn having a DLC coating on its tip (Test No. 4-3), the life of the horn was further improved.
以上の結果からわかるように、本発明によれば、超音波接合によって同種の鋼板同士を接合しても十分な接合強度を得ることが可能な超音波接合用鋼板、超音波接合用高強度鋼板及び超音波接合方法を提供することができる。 As can be seen from the above results, according to the present invention, ultrasonic bonding steel sheets and high-strength steel sheets for ultrasonic bonding, which can obtain sufficient bonding strength even when the same type of steel sheets are bonded to each other by ultrasonic bonding. And ultrasonic bonding methods can be provided.
１０ 試験片
２０ 接触部
10 Test piece 20 Contact part
Claims (9)
前記鋼板の少なくとも１つが、請求項１〜５のいずれか一項に記載の超音波接合用鋼板又は請求項６に記載の超音波接合用高強度鋼板であり、
前記超音波接合が、周波数：２０〜４０ｋＨｚ、出力：８００Ｗ以上、加圧時間：０．２秒以上、加圧力：５００〜２０００Ｎの条件で行われる超音波接合方法。 A method of ultrasonically bonding two or more steel sheets.
At least one of the steel sheets is the ultrasonic bonding steel sheet according to any one of claims 1 to 5 or the ultrasonic bonding high-strength steel sheet according to claim 6.
An ultrasonic bonding method in which the ultrasonic bonding is performed under the conditions of frequency: 20 to 40 kHz, output: 800 W or more, pressurizing time: 0.2 seconds or more, and pressing force: 500 to 2000 N.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001205452A (en) * | 2000-01-24 | 2001-07-31 | Toshiba Corp | Ultrasonic welding equipment, ultrasonic welding method, closed battery and producing method thereof |
| JP2003266180A (en) * | 2002-03-14 | 2003-09-24 | Nissan Motor Co Ltd | Tool and equipment for ultrasonic welding |
| JP2007009235A (en) * | 2005-06-28 | 2007-01-18 | Sumitomo Metal Ind Ltd | Steel sheet with excellent workability, and its manufacturing method |
| JP2008080383A (en) * | 2006-09-28 | 2008-04-10 | Kobe Steel Ltd | Ultrasonic bonding method for ultra-fine grained steel plate |
| WO2013088692A1 (en) * | 2011-12-12 | 2013-06-20 | Ｊｆｅスチール株式会社 | Steel sheet with excellent aging resistance, and method for producing same |
| WO2017029815A1 (en) * | 2015-08-19 | 2017-02-23 | Ｊｆｅスチール株式会社 | High-strength steel sheet and production method for same |
| JP2018094604A (en) * | 2016-12-14 | 2018-06-21 | 日新製鋼株式会社 | Ultrasonic bonding method |
-
2019
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Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001205452A (en) * | 2000-01-24 | 2001-07-31 | Toshiba Corp | Ultrasonic welding equipment, ultrasonic welding method, closed battery and producing method thereof |
| JP2003266180A (en) * | 2002-03-14 | 2003-09-24 | Nissan Motor Co Ltd | Tool and equipment for ultrasonic welding |
| JP2007009235A (en) * | 2005-06-28 | 2007-01-18 | Sumitomo Metal Ind Ltd | Steel sheet with excellent workability, and its manufacturing method |
| JP2008080383A (en) * | 2006-09-28 | 2008-04-10 | Kobe Steel Ltd | Ultrasonic bonding method for ultra-fine grained steel plate |
| WO2013088692A1 (en) * | 2011-12-12 | 2013-06-20 | Ｊｆｅスチール株式会社 | Steel sheet with excellent aging resistance, and method for producing same |
| WO2017029815A1 (en) * | 2015-08-19 | 2017-02-23 | Ｊｆｅスチール株式会社 | High-strength steel sheet and production method for same |
| JP2018094604A (en) * | 2016-12-14 | 2018-06-21 | 日新製鋼株式会社 | Ultrasonic bonding method |
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