JP2004082644A - Intellectual molding system for thermosetting resin molding material and intellectual composing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain the generation of residual stress without reducing production efficiency. <P>SOLUTION: The intellectual molding system for a thermosetting resin composite material comprises an autoclave 3, a calculator 7, an adjusting device 4 for adjusting the environmental temperature T<SB>1</SB>in the autoclave 3, a molding object 9 to be formed of a thermosetting resin composite material in the autoclave 3, a first temperature measuring device 13 for measuring the environment temperature T<SB>1</SB>, and a second temperature measuring device 15 for measuring the target temperature T<SB>2</SB>of the molding target 9. The calculating device 7 obtains a parameter by calculation, making the thermal balance equation a simultaneous equation for a plurality of times. On the basis of the same equation, an expected target temperature after the present time is calculated, based on which a control value 19 for controlling the environment temperature is output. Based on the present physical quantities out of and within its own learned, the future physical quantities out of and within its own are controlled according to a physical law to precisely control the molding of the thermosetting resin composite material so far hard to be controlled. Such a control is almost imppossible without calculation. <P>COPYRIGHT: (C)2004,JPO

Description

反応熱は、次式で与えられる。
Ｉｃ・ρｃ・Ｑ・ｒ（Ｔｃ，α）［Ｊ／ｍ２・ｓ］
【００２７】
ここで、合理的に次式が近似的に仮定される。
ｄＴｆ／ｄｔ＝ｄＴｃ／ｄｔ＝ｄＴｍ／ｄｔ
この仮定に基づけば、

この式は、次式で簡素に表現される：
Ａ・（ｄＴｃ／ｄｔ）＝２ｈｔ（Ｔｂ−Ｔｃ）＋Ｂ・ｒ（Ｔｃ，α）・・・（１）
ここで、Ａは１つの定数として扱われ、Ｂは他の１つの定数として扱われる。
Ａ＝Ｉｆ・Ｃｐｆ・ρｆ＋Ｉｃ・Ｃｐｃ・ρｃ＋Ｉｍ・Ｃｐｍ・ρｍ
Ｂ＝Ｉｃ・ρｃ・Ｑ
式（１）の中のα（＝∫（ｄα／ｄｔ）ｄｔ）は、後述されるように常態的に計算されていて既知である。
【００２８】
式（１）のパラメータＡ，Ｂは、次に記述されるように求められて既知になる。既述の第１温度計測器１３と第２温度計測器１４とによりＴｂ，Ｔｃを昇温過程で一定周期（ｎΔｔ：ｎは１，２・・・）で計測することにより下記の３つの値を知ることにより決定される。
δＴ_（ｎ）　←　Ｔｂ_（ｎ）−Ｔｃ_（ｎ）
ｄＴｃ／ｄｔ｜_（ｎ）　←　（Ｔｃ_（ｎ）−Ｔｃ_{（ｎ−１）}）／Δｔ
ｒ_（ｎ）　←　ｒ（Ｔｃ_（ｎ），α_（ｎ））
【００２９】
このような計測される値に基づいて、ｎ＝１以降のｎについて、下記連立方程式計算器７でリアルタイムに解かれて、２ｈｔ／Ａと、Ｂ／Ａが求められる。
δＴ_（ｎ）・２ｈｔ／Ａ＋ｒ_（ｎ）・（Ｂ／Ａ）＝ｄＴｃ／ｄｔ｜_（ｎ）
δＴ_{（ｎ−１）}・２ｈｔ／Ａ＋ｒ_{（ｎ−１）}・（Ｂ／Ａ）＝ｄＴｃ／ｄｔ｜_{（ｎ−１）}
【００３０】
このように決定される２ｈｔ／Ａと、Ｂ／Ａが用いられて、以降のＴｃの予測が可能である。
ｄＴｃ／ｄｔ＝（２ｈｔ／Ａ）・（Ｔｂ−Ｔｃ）＋（Ｂ／Ａ）・ｒ（Ｔｃ，α）・・・（２）
Ｔｂについて種々の昇温速度を仮定して、式（２）からＴｃの変化を予測することにより、温度Ｔｃの最大値が許容値を下回るような温度Ｔｂの昇温速度が探索され、Ｔｂが新たに設定される。このＴｂの設定は、時間間隔Δｔの程度の間隔で、実質的にリアルタイムで実行され得る。このような設定のアルゴリズムが、時間的に実質的に連続的に繰り返され、希望する昇温速度を熱硬化成形対象９に与えることができる。
【００３１】
硬化度αの硬化速度ｄα／ｄｔは、Ｓｐｒｉｎｇｅｒ　らの熱化学モデル（Ｐ．Ｒ．Ｃｉｒｉｓｃｉｏｌｉ　ａｎｄ　Ｇ．Ｓ．Ｓｐｒｉｎｇｅｒ．　”Ｓｍａｒｔ　Ａｕｔｏｃｌａｖｅ　Ｃｕｒｅ　ｏｆ　Ｃｐｍｐｏｓｉｔｅｓ”，　Ｔｅｃｈｎｏｍｉｃ　Ｐｕｂｌｉｓｈｉｎｇ　Ｃｏ．　Ｉｎｃ．，１９９０）により定式化されている。ｄα／ｄｔ＝（Ｈ_Ｔ／Ｈ_Ｕ）・（１／Ｈ_Ｔ）・（ｄＱ／ｄｔ）_Ｔ・・・（３）
αは、０と１の間の無次元変数であり、１００が乗じられて％で表され得る。Ｈ_Ｕは等速昇温の示差熱走査分析で得られる全反応熱であり、Ｈ_Ｔは等温加熱の示差熱走査分析で得られる反応熱であり、ｄＱ_Ｔ／ｄｔは発熱速度である。ここで、等温反応速度ｄβ／ｄｔが以下にに定義される。
【００３２】
ｄβ／ｄｔ＝（１／Ｈ_Ｔ）・ｄＱ／ｄｔ）_Ｔ
ｄβ／ｄｔは、温度Ｔ（Ｋ）とβの関数として次式で表される。
ｄβ／ｄｔ＝（ｋ_１＋ｋ_２β^ｍ）・（１−β）^ｎ
ｋ_１＝Ａ_１ｅｘｐ（−Ｅ_１／ＲＴ）
ｋ_２＝Ａ_２ｅｘｐ（−Ｅ_１／ＲＴ）
ここで、Ａ_１，Ａ_２，Ｅ_１，Ｅ_２，ｍ，ｎは定数であり、Ｒは気体定数である。βに関する微分方程式からβが求められｄβ／ｄｔが決定され、ｄβ／ｄｔに基づいて硬化速度ｄα／ｄｔが求められ、硬化速度の積分により、硬化度αが求められる。
【００３３】
光ファイバ歪センサ１５としては、下記（１）又は（２）のセンサが好適に用いられ得る。
（１）ＥＦＰＩ−ＦＯＳＳＩＩ−０４−Ｐ−Ｅ（Ｆｉｂｅｒ　＆　Ｓｅｎｓｏｒ　Ｔｅｃｈｎｏｌｏｇｉｅｓ　社製）
（２）ＦＯＳ−５０００３−Ｎ　（ＦＩＳＯ　Ｔｅｃｈｎｏｌｏｇｉｅｓ　社製）
これらは、いずれもがＥＦＰＩ（Ｅｘｔｒｉｎｓｉｃ　Ｆａｂｒｙ−Ｐｅｒｏｔ　Ｉｎｔｅｒｆｅｒｏｍｅｔｅｒ，外因性ファブリ・ペロー型干渉計）であり、入出力側光ファイバーと反射側ファイバーとが器具本体に固定されて装着され、両ファイバーの間には空隙が与えられ、両ファイバーの対向端面が平行平面に形成されてファブリ・ペロー干渉計が形成され、隙間の間隔の変動による干渉光の量又はピーク波長の変動に基づいて、歪を測定する周知の高性能・高精度計測器である。
【００３４】
硬化度は、誘電センサにより直接的に計測され得る。誘電センサは、硬化度に対応するイオン粘度を計測する周知の計測器である。誘電センサは、硬化に起因して生じる電気分極に対応する電気的センサ応答の位相のずれと振幅を計測し、その位相のずれと振幅とに基づいて比誘電率ε（＝ε’−ｉε”）の虚数部として定義される損失係数ε”を求め、ε”＝ρ／（ω・ε_０）で表される関係式で定められるイオン粘度（＝（１／ρ）・オームｃｍ）を計測する。ここで、ρはイオン伝導率、ωは印加電場の角速度、ε_０は真空中の誘電率である。その硬化度は、光ファイバ歪センサにより補正され得る。発明者らは、特定の熱硬化樹脂を用いて、硬化過程の比体積の変化を測定し、比体積を温度と硬化度の関数として記述する式を導出し、硬化度が一定の値に達した時点で硬化収縮が終了し、硬化温度が一定に保たれている領域にある場合に、比体積も一定になることを見出した。この時点は、光ファイバ歪センサにより検出される。この時点の硬化度は温度に依存して一意に定まり、この時点の硬化度を正確に算出することができる。
【００３５】
本発明による熱硬化樹脂系複合材の知的成形方法の実施の形態は、下記ステップにより実行される。
ステップ１：
成形対象物体の複数箇所に温度計特に２つの温度計である第１温度計測器１３と第２温度計測器１４とが配置され、温度Ｔｂと温度Ｔｃが計測される。更に、光ファイバ歪センサ１５が配置され、歪みが測定されることは好ましい。
【００３６】
ステップ２：
時間を関数とする設定温度Ｔ（ｔ）が、計算器７に理想的に設定される。その温度設定が理想的であることは、過去の事例的経験又は理論的解析から分かっていて、特に、硬化反応熱発生に起因する急激な温度上昇が悪影響を与えることが分かっている。
【００３７】
ステップＳ３：
硬化度αは、計算器７の中にプログラム化されている硬化反応速度式（３）に基づいてリアルタイムに計算されている。又は、硬化度は過去の事例から経験則的に得られ、温度と時間の関数として知られていて、その硬化度αは温度と時間とに対応する値としてテーブル化されている。計算器７は、そのようなテーブルを有している。硬化度αは、更には、誘電センサにより直接的に計測され得る。硬化速度は、硬化度から求められる。その硬化度αは、光ファイバ歪センサによりその値が補正され得る。
【００３８】
ステップＳ４：
温度差（Ｔｂ−Ｔｃ）が、計算器７により求められる。複数時刻の実測値に基づく連立方程式（１）又は式（２）により、ｈｔ／ＡとＢ／Ａの２つのパラメータが計算器７により計算されて高精度に決定される。式（２）のαは既に求められていて、ｒ（Ｔｃ，α）が既知になっている。
【００３９】
ステップＳ５：
その計算により総括電熱係数ｈｔと他のパラメータ（単位面積・硬化速度当たりの反応熱量Ｑ）が決定されれば、式（１）に基づいて任意の時刻の温度変化ｄＴｃ／ｄｔが計算され、その積分により任意の時刻の温度Ｔｃが計算により求められる。Ｔｂについて種々の昇温速度を仮定してその計算を繰り返すことにより、昇温速度に依存したＴｃの最大値Ｔｃｍａｘが求められる。
【００４０】
ステップＳ６：
設定された温度サイクルの通りにＴｂを昇温させた場合に、ＴｃｍａｘがＴｃの許容最高温度を越えると予想される場合には、ＴｃｍａｘがＴｃの許容最高温度を越えない範囲で最大の昇温速度を選択し、その昇温速度に基づいて設定温度Ｔｂを設定し直す。式（２）には硬化反応熱が組み込まれているので、硬化反応熱が組み込まれている式（２）が算出する予測温度に対応して、圧力容器３の中の加圧媒体６の温度を制御することにより、温度Ｔｃを式（２）が予測する温度に調整することができ、特に温度Ｔｃが許容最高温度を越えることがないように常態的に制御することができる。その後に、Ｔｂが設定された硬化温度（保持温度）に達した時点で、一定温度の保持され、更にその後に、硬化度αが硬化終点を示す所定の値に達した時点で、設定された昇温速度でＴｂの降温が開始される。硬化度αがその値に達する以前の段階で、光ファイバ歪センサの計測値に基づいて、硬化度αの値を補正することができる。
【００４１】
実施例：
カーボン繊維／耐熱タフエポキシ系樹脂プリプレグ（三菱レイヨン社製：ＭＲ５０Ｋ／＃９８２）の８８プライの内部に、既述の光ファイバセンサが埋め込まれ、オートクレーブ成形され、オートクレーブ成形過程の内部状態センシング（硬化モニタリング）が本発明者により試みられた。
【００４２】
図４は、本発明による熱硬化樹脂系複合材の知的成形方法により温度制御された硬化過程の実測データを示している。横軸は分を示し、左側縦軸は温度と硬化度（％）を示し、右側縦軸は歪を示している。点線表示の曲線（イ）は、標準的な設定温度を示している。曲線（ロ）は、成形対象の実測温度Ｔｃを示している。曲線（ハ）は、比体積の計算式から計算された比体積を示している。曲線（ニ）は、硬化反応速度式から求められた硬化度を示している。曲線（ホ）は、光ファイバ歪センサにより測定された歪みを示している。曲線（ヘ）は、硬化収縮終了時刻を示している。硬化度は、最終的に１（１００％）に漸近する。
【００４３】
公知技術によれば、図１０（ｂ）に示されるように、硬化反応に伴う発熱により突然的に過昇温になることがあるが、本発明による熱硬化樹脂系複合材の知的成形方法によれば、図４の曲線（ロ）に示されるように、設定温度（イ）を越えて高く上昇することはない。
【００４４】
図５は、本発明による熱硬化樹脂系複合材の知的成形方法の実施の他の形態を示している。図５に示されるように、オートクレーブ３の加圧媒体６の温度制御（ト）の温度上昇速度をより緩やかに設定すれば、硬化反応熱の影響を受けて、制御対象温度（ロ）が設定温度（イ）を上回ることがあるが、その過昇温の程度は小さい。本発明による熱硬化樹脂系複合材の知的成形方法によれば、図６に示されるような急峻な硬化反応速度（ｃｕｒｅ　ｒａｔｅ）（チ）が現れず、過昇温と残留応力を効果的に抑制することができる。
【００４５】
図４は、曲線（ホ）により示される歪みの変化が概ね零になる時間領域に硬化収縮点Ｐが存在していることを示している。図７は、比体積（Ｓｐｅｃｉｆｉｃ　Ｖｏｌ．）の変化曲線を追加的に示す一般的なグラフである。適正に制御される温度上昇曲線が変化しない時間領域に入った後に、比体積曲線（チ）も変化しない状態に入る。比体積と歪みとが一定値になる時点は、硬化収縮終了時点Ｐに概ね一致している。硬化は、硬化収縮終了時点の後に更に進む。硬化度が１（１００％）に十分に近づた点Ｑを温度保持ステップ終了時点とし、温度降下の制御が開始される。
【００４６】
図８は、硬化収縮終了時点をより厳密に知ることができる手段を示し、本発明者により見出された比体積の温度と硬化度に対する依存性から求められた硬化過程の比体積変化示している。図８は、比体積の時間１階微分変化曲線（リ）と比体積の時間２階微分変化曲線（ヌ）とを更に追加的に示している。時間１階微分変化曲線（リ）が一定値を維持した後に急減する時点に遅れて、時間２階微分変化曲線（ヌ）が発散的にピーク値を示す。そのピーク値を示す時点は、硬化収縮終了時点Ｑに高精度に一致している。時間１階微分変化曲線（リ）が安定的に零を維持する無変化状態（ル）に入ったことが確認された後に、時間的に遡って時間２階微分変化曲線（ヌ）がピーク値を持つ時点を探索することにより、硬化収縮終了時点Ｑを高精度に見定めることができる。
【００４７】
図９（ａ），（ｂ）は、歪み（Ｓｔｒａｉｎ）と、歪みの時間１階微分変化曲線（オ）と、歪みの時間２階微分変化曲線（ワ）とをそれぞれに示している。歪みの１階微分と２階微分は、
ｄＳ／ｄｔ＝｛Ｓ（ｔ）−Ｓ（ｔ−Δｔ）｝／Δｔ
ｄＳ^２／ｄｔ^２＝｛ｄＳ（ｔ）／ｄｔ−ｄＳ（ｔ−Δｔ）／ｄｔ｝／Δｔ
により求められる。Ｓは歪を表わす。Δｔ＝２分の場合は（ａ）で、Δｔ＝２０分の場合は（ｂ）で示されている。Δｔ＝２分では、硬化収縮終了時点Ｑとの間に実用的な相関性は見られないが、Δｔ＝２０分では、時間１階微分変化曲線が安定的に零を維持する無変化状態に入ったことが確認された後に、時間的に遡って時間２階微分変化曲線がピーク値を持つ時点を探索し、更にその時点よりΔＴ（２０分）遡った時点を硬化収縮終了時点Ｑとして定めることができる。図１１と図１２は、既述の制御手順を記述するフローチャートを示している。
【００４８】
【発明の効果】
本発明による熱硬化樹脂系複合材の知的成形システム、及び、その知的成形方法は、生産効率を低下させずに反応熱による温度の異常上昇と硬化収縮による残留応力を抑制する技術を確立することができる。
【図面の簡単な説明】
【図１】図１は、本発明による熱硬化樹脂系複合材の知的成形システムの実施の形態を示すシステムブロック図である。
【図２】図２は、成形装置を示す断面図である。
【図３】図３は、温度測定位置示す断面図である。
【図４】図４は、温度変動と硬化度等との関係を示すグラフである。
【図５】図５は、３つの温度変動を示すグラフである。
【図６】図６は、公知の温度変動と硬化速度を示すグラフである。
【図７】図７は、温度変動と比体積の一般的な関係を示すグラフである。
【図８】図８は、比体積変化と硬化収縮終了時点の相関性を示すグラフである。
【図９】図９（ａ），（ｂ）は、歪みと硬化収縮終了時点の相関性をそれぞれに示すグラフである。
【図１０】図１０（ａ），（ｂ）は、公知の設定温度と実測温度をそれぞれに示すグラフである。
【図１１】図１１は、本発明による知的成形制御手順の実施の形態を示すフローチャートである。
【図１２】図１２は、本発明による知的成形制御手順の実施の他の形態を示すフローチャートである。
【符号の説明】
３…オートクレーブ
４…調節器
６…加圧媒体
７…計算器
９…成形対象
１３…第１温度計測器
１５…第２温度計測器
１９…制御値[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to an intelligent molding system for a thermosetting resin-based composite material and an intelligent molding method thereof, and particularly to a thermosetting resin-based composite material for manufacturing a large structure such as a hull structure, an aircraft structure, and a windmill blade. And an intelligent molding method for the same.
[0002]
[Prior art]
The use of the thermosetting reinforced composite material in which a resin and a reinforcing fiber are composited is expanding in various fields. As an application thereof, application to a large structure such as a hull structure, an aircraft structure, and a windmill wing has attracted attention. Autoclave molding in which heating is performed under pressure is known as a molding technique of a thermosetting resin-based composite material.
[0003]
The autoclave molding process of the composite material includes a heating step, a temperature holding step, and a cooling step. FIG. 10A illustrates a standard temperature cycle. In the curing process, an exothermic chemical reaction generally occurs. The cured material is subjected to heating based on the ambient temperature in the autoclave and heating based on self-heating. As shown in FIG. 10B, an overheating phenomenon based on overheating occurs due to a combination of such both heating. Such an excessive temperature rise causes a decrease in the strength of CFRP (carbon-based) or GFRP (glass-based) after molding. According to the overheating experiment, it is known that the compressive strength and the interlaminar shear strength decrease. If the heating rate is slow, excessive heating is avoided, but if the heating rate is slow, the molding time is long. Conventionally, control has been performed based on a measurement value of a temperature sensor attached to a molding target, and “material temperature control” in which the molding target is maintained at a desired temperature has been generally performed. In such a case, the amount of heat generated per unit area becomes large, and there is a possibility that the cooling capacity of the autoclave cannot be sufficiently controlled.
[0004]
Thermosetting resins generally undergo curing shrinkage during curing. In the process of shifting from the curing temperature to room temperature, thermal contraction occurs due to the difference in thermal expansion. Such a change in the volume of the resin causes the residual stress of the FRP. The FEM analysis of the residual stress due to curing shrinkage and thermal expansion contained in the specific volume change of the resin was used in place of the expansion and contraction rate predicted from the specific volume change, and analyzed by the present inventors. Analysis that assumes that the fluidity of the resin completely disappears when the degree of cure reaches 40% indicates that the matrix resin shrinks more than carbon fiber and the tensile stress acts in the composite material. ing. In an analytical test in which 0.2 ° C./min and 2.0 ° C. were selected as the heating rate, the residual stress at 0.2 ° C./min was half of the residual stress at 2.0 ° C./min. there were.
[0005]
The residual stress causes defects such as cracks in the compact. Excessive suppression of the rate of temperature rise, which reduces production efficiency, does not provide a practical solution for suppressing crack defect generation. It is desired that the curing be promoted at a heating rate in consideration of the production efficiency and that the excessive heating phenomenon is not exhibited. Material temperature control for detecting an excessive temperature rise and cooling an autoclave to lower its ambient temperature is known. Material temperature control cannot effectively suppress the occurrence of crack defects. Although the need for a heating algorithm that does not cause the excessive heating phenomenon has been noticed, no specific plan for the heating algorithm is disclosed.
[0006]
It is required to establish a technique for suppressing excessive temperature rise and residual stress without lowering production efficiency.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide an intelligent molding system for a thermosetting resin-based composite material capable of establishing a technique for suppressing excessive heating and residual stress without lowering production efficiency, and an intelligent molding method thereof. Is to do.
[0008]
[Means for Solving the Problems]
Means for solving the problem are expressed as follows. The technical items appearing in the expression are appended with numbers, symbols, etc. in parentheses (). The numbers, symbols, and the like are technical items that constitute at least one embodiment or a plurality of embodiments of the embodiments or the embodiments of the present invention, in particular, the embodiments or the embodiments. Corresponds to the reference numbers, reference symbols, and the like assigned to the technical matters expressed in the drawings corresponding to. Such reference numbers and reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters of the embodiments or examples. Such correspondence / bridge does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments or the examples.
[0009]
The intelligent molding system for thermosetting resin-based composites according to the present invention comprises an autoclave (3), a calculator (7), and an environmental temperature T in the autoclave (3).₁Controller (4) for adjusting the ambient temperature T₁Temperature measuring device (13) for measuring the temperature, and a target temperature T of a molding object (9) formed from a thermosetting resin-based composite material in an autoclave (3).₂And a second temperature measuring device (15) for measuring the temperature. The calculator (7) calculates the heat balance equation: dT₂/ Dt = P₁・ (T₁-T₂) + P₂・ R (T₂, Α)
P₁: Parameter
P₂: Parameter
r: known curing reaction rate
α: known degree of cure
To obtain the parameters by calculation by simultaneous equations as equations of a plurality of times, and to calculate the temperature to be predicted after the current time based on the same equation, and to control the environmental temperature based on the temperature to be predicted. Is output to the controller (4).
[0010]
It measures the temperature difference between two positions (external and internal), which is a physical phenomenon based on the heat (internal heat) released by itself from the heat given from the outside, in real time, and gives it from its own curing heat and atmosphere. The above-mentioned temperature difference after the current time is predicted based on the heat to be applied, and intelligent control for asymptotically bringing the temperature of the molding target closer to the set temperature becomes possible. Here, the intelligent control means controlling the future physical quantity outside the self and the future physical quantity inside the self in accordance with the physical laws by knowing the current physical quantities outside the self and inside the self, and changing the initial conditions of the physical laws. Control, not just feedback control, and not just feedforward control. Although empirical rules are important, control based on the laws of physics is basically performed, and it is possible to control strictly asymptotically to the set temperature, and high-performance physical properties of thermosetting resin-based composite materials that were difficult to control Can be obtained with high accuracy.
[0011]
The degree of cure α is determined by the calculator (7) by integrating a curing reaction rate equation expressing the curing rate dα / dt as a function of the temperature and the degree of cure α. The degree of cure α can be corrected by an optical fiber strain sensor (15) that measures the internal strain of the molding target (9).
[0012]
Preferably, an optical fiber strain sensor (15) is used in addition to the first temperature measuring device (13) and the second temperature measuring device (15). Temperature measurement positions are not limited to two positions. Increasing the number of measurement positions configures a larger number of simultaneous equations to increase the calculation accuracy. As the optical fiber strain sensor, a Fabry-Perot interferometer type is preferably used. The first temperature measuring device (13) measures the temperature of the atmospheric gas in the autoclave (3), and the second temperature measuring device (15) measures the temperature at a specific position on the surface or inside the molding target.
[0013]
The intelligent molding method of a thermosetting resin-based composite material according to the present invention comprises the steps of: increasing the ambient temperature in the autoclave (3);₁And the target temperature T of the molding object (9) in the autoclave.₂Calculating the predicted temperature of the molding object (9) after the current time based on the heat balance equation describing the change of the temperature, and when the maximum value of the predicted object temperature exceeds the allowable maximum temperature, the temperature rise rate is calculated. Calculating the predicted temperature when the temperature is reduced, searching for the maximum heating rate under the condition that the maximum value does not exceed the maximum allowable temperature, and calculating the maximum value of the predicted temperature exceeding the maximum allowable temperature. The ambient temperature T based on the searched heating rate.₁From the step of controlling the temperature by the controller (4), the step of keeping the ambient temperature constant when the predetermined curing temperature is reached, and the step of lowering the ambient temperature when the curing degree α reaches the predetermined value. It is configured.
[0014]
Molding of thermosetting resin-based composite materials that were difficult to control by intelligent control that controls the physical quantity of the future outside the self and the physical quantity inside the self according to the laws of physics by knowing the current physical quantity inside and outside the self Can be controlled with high accuracy.
[0015]
The step of measuring the strain of the molding object (9), the step of calculating the hardening / shrinking completion time point (P) corresponding to the time point at which the change of the strain becomes small by the calculator (7), and the hardening / shrinking completion time point (P) The step of determining the end time of the transition step based on the above is effectively added. The curing shrinkage completion time (P) known from these two steps is important data for accurately predicting the end time of the transition step.
[0016]
Calculating the first derivative of the distortion with respect to time by the calculator and calculating the second derivative of the distortion with respect to the time by the calculator are even more effectively added. The time point at which the curing shrinkage is completed is identified as a time point at which the first-order derivative approaches substantially zero and the second-order derivative reaches a peak in a temperature holding step in which the autoclave atmosphere temperature is kept constant. Tracking changes in the first and second derivatives of strain is important data for more tightly controlling the start of the descent step to lower the temperature by more precisely knowing the end of cure shrinkage. The Fabry-Perot interferometer type optical fiber is most suitable as the measuring instrument (15) required for such strict control.
[0017]
The distortion is composed of distortion due to curing contraction and distortion due to thermal expansion contraction. Therefore, the specific volume is described by a two-variable function using the temperature and the degree of cure as variables. In the temperature holding step in which the temperature of the autoclave atmosphere is held constant, the time point at which the strain becomes a constant value is identified with high precision at the time point of curing and shrinking. The degree of cure at the end of cure shrinkage is uniquely determined only by the temperature from the equation describing the specific volume. By knowing the end point of curing shrinkage, the degree of curing at that point can be accurately known, and errors in the degree of curing determined by integration of the curing reaction rate equation can be corrected. As a result, the curing end point can be determined with high accuracy, the curing time can be kept to a minimum, and the production efficiency can be increased.
[0018]
An intelligent molding system for a thermosetting resin composite material according to the present invention includes a step of increasing an ambient temperature in an autoclave (3); and a step of maintaining an ambient temperature constant when a predetermined curing temperature is reached. Measuring the ambient temperature in the autoclave (3), measuring the target temperature of the object to be molded in the autoclave (3), integrating the curing reaction rate equation to obtain the degree of cure α, Measuring the internal strain of the target with an optical fiber strain sensor, calculating the time first derivative of the internal strain, calculating the time second derivative of the internal strain, and keeping the autoclave ambient temperature constant A step of searching for a point in time at which the second derivative reaches a peak value after the first derivative stably reaches a zero value state in the temperature holding step; A step of identifying as a cure shrink end time (Q), and a step of replacing the cure degree α obtained by integrating the cure reaction rate equation with a cure degree corresponding to the cure shrink end time (Q). Starting from the curing degree α, the curing reaction rate equation is again integrated to obtain the curing degree α, and the step of lowering the ambient temperature when the curing degree α reaches a predetermined value. . The degree of cure is corrected based on the end point of curing shrinkage (Q), and the point at which the temperature starts to decrease is determined with high accuracy, thereby improving the physical properties of the product and reducing the curing cycle time to the necessary minimum. Can be suppressed.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Corresponding to the figures, an embodiment of the intelligent molding system for thermosetting resin-based composites according to the present invention is provided with an autoclave together with a temperature cycle controller. The temperature and pressure of the autoclave 1 are adjusted by a temperature cycle controller 2 as shown in FIG. The autoclave 1 forms a pressure vessel 3. The temperature cycle controller 2 has a temperature controller 4. The temperature cycle controller 2 has an operation control program 5. The temperature controller 4 operates according to the operation control program 5 and controls the temperature of the pressurized medium 6 in the pressure vessel 3. The temperature cycle controller 2 further comprises a calculator 7 having an intelligent molding control program. Between the operation control program 5 and the calculator 7, a network shared file 8 for exchanging data is provided.
[0020]
The thermosetting molding object 9 is hermetically packaged in a pressure vessel 3 with a molding jig 11 and a film or sheet-like bag material 12, and the inside thereof is placed in a decompressed state. For temperature measurement, a first temperature measuring instrument 13 and a second temperature measuring instrument 14 are used. Further, another temperature measurement is added. An optical fiber strain sensor 15 is used for measuring the internal strain of the molding object 9. The first temperature measuring device 13 measures the ambient temperature Tb in the pressure vessel 3. The second temperature measuring device 14 measures the temperature Tc of the thermosetting molding object 9. The added temperature measuring device measures the temperature of the molding jig 11 and another position of the molding target 9. The optical fiber strain sensor 15 measures the internal strain of the molding object 9 due to a change in volume due to the curing shrinkage of the resin and the difference in thermal expansion.
[0021]
The temperature cycle controller 2 further has a recorder 17. The recorder 17 includes an ambient temperature Tb output from the first temperature measuring device 13, a temperature Tc of the molding target 9 output from the second temperature measuring device 14, and a molding target 9 output from the added temperature measuring device. , The temperature of the molding jig 11, and the internal strain of the molding object 9 output by the optical fiber distortion sensor 15.
[0022]
The measurement data 18 formed from the temperature and strain calculated and recorded in this way is recorded and shared in the shared file 8 in the network, and further transmitted to the calculator 7. The calculator 7 calculates an optimum temperature increase cycle based on the measurement data 18 and generates set value data 19. The set value data 19 is shared by the network shared file 8 and transmitted to the temperature controller 4 by the measurement data 18. The temperature controller 4 controls the ambient temperature Tb in the pressure vessel 3 based on the set value data 19.
[0023]
FIG. 2 shows heat conduction between a plurality of parts. Due to the heat conduction between the first representative portion 21 of the pressurized medium 6 and the second representative portion 22 on the outer surface of the bag material 12, the second representative portion 22 separates the heat of the pressure vessel 3 from the pressurized medium 6. And has a temperature Tf. Due to heat conduction between the second representative portion 22 of the bag material 12 and the third representative portion 23 of the thermosetting molding object 9, the third representative portion 23 receives heat from the bag material 12 and has a temperature Tc. . Due to the heat conduction between the fourth representative portion 24 of the molding jig 11 and the inner surface of the thermosetting molding target 9, the fourth representative portion 24 receives heat from the thermosetting molding target 9 or the pressurized medium 6. It has a temperature Tm. An arbitrary one-point region 25 in the thermosetting molding object 9 is subjected to deformation due to curing shrinkage deformation and a difference in thermal expansion, and a strain force is generated there. The temperature Tb will be controlled.
[0024]
The calculator 7 describes the following mathematical formula group. FIG. 3 shows the physical property values for each region. The physical properties of the bag material 12, the thermosetting molding object 9 and the molding jig 11 are indicated by the following symbols.
Physical properties of bag material 12:
If: the thickness [m] of the bag material 12
Cpf: Specific heat of bag material 12 [J / kg · K]
ρf: Density of bag material 12 [kg / m³]
Physical property values of thermosetting molding object 9:
Ic: thickness [m] of thermosetting molding object 9
Cpc: Specific heat of thermosetting molding object 9 [J / kg · K]
ρc: density of the thermosetting molding object 9 [kg / m³]
Physical property values of molding jig 11:
Im: thickness [m] of the molding jig 11
Cpm: Specific heat of the molding jig 11 [J / kg · K]
ρm: density of the molding jig 11 [kg / m³]
[0025]
Further, other physical property values are indicated by the following symbols.
h: Heat transfer coefficient of film in the vicinity of the surfaces of the bag material 12 and the forming jig 11 [W / m]²・ K]
ht: Overall heat transfer coefficient [W / m] of the pressurized medium 6 with respect to all member surfaces²・ K]
t: time [s]
Q: Reaction heat per unit prepreg mass [J / kg]
r (Tc, α): curing reaction rate (s^-1) (Described below)
α: Hardness degree [Dimensionless] (described later)
[0026]
The heat input transmitted from the pressurized medium 6 to the thermosetting molding object 9 is given by the following equation. 2 ht (Tb-Tc) [J / m²・ S]
The increase in the calorific value of the member is given by the following equation.

The heat of reaction is given by:
Ic · ρc · Q · r (Tc, α) [J / m2 · s]
[0027]
Here, the following equation is reasonably assumed approximately.
dTf / dt = dTc / dt = dTm / dt
Based on this assumption,

This expression is simply expressed as:
A · (dTc / dt) = 2ht (Tb−Tc) + B · r (Tc, α) (1)
Here, A is treated as one constant, and B is treated as another constant.
A = If · Cpf · ρf + Ic · Cpc · ρc + Im · Cpm · ρm
B = Ic · ρc · Q
Α (= ∫ (dα / dt) dt) in the equation (1) is normally calculated and known as described later.
[0028]
The parameters A and B in equation (1) are determined and known as described below. The following three values are obtained by measuring Tb and Tc at a constant period (nΔt: n = 1, 2,...) During the temperature rise process using the first temperature measuring device 13 and the second temperature measuring device 14 described above. Is determined by knowing.
δT_(N)← Tb_(N)-Tc_(N)
dTc / dt |_(N)← (Tc_(N)-Tc_(N-1)) / Δt
r_(N)← r (Tc_(N), Α_(N))
[0029]
On the basis of such measured values, the following simultaneous equation calculator 7 solves in real time for n after n = 1 to obtain 2 ht / A and B / A.
δT_(N)・ 2ht / A + r_(N)・ (B / A) = dTc / dt |_(N)
δT_(N-1)・ 2ht / A + r_(N-1)・ (B / A) = dTc / dt |_(N-1)
[0030]
Using the 2 ht / A and the B / A determined in this way, the subsequent Tc can be predicted.
dTc / dt = (2 ht / A) · (Tb−Tc) + (B / A) · r (Tc, α) (2)
Assuming various heating rates for Tb, by predicting a change in Tc from equation (2), a heating rate of the temperature Tb is searched for such that the maximum value of the temperature Tc falls below the allowable value, and Tb is determined. It is newly set. This setting of Tb can be performed substantially in real time at intervals of the order of the time interval Δt. The algorithm of such a setting is repeated substantially continuously in time, and a desired heating rate can be given to the thermosetting molding object 9.
[0031]
The curing rate dα / dt of the degree of cure α is determined by the thermochemical model of Springer et al. (PR Ciriscioli and G. S. Springer. “Smart Autoclave Cure of Cpmposties”, Technomic {Publication. Have been. dα / dt = (H_T/ H_U) ・ (1 / H_T) ・ (DQ / dt)_T... (3)
α is a dimensionless variable between 0 and 1, which can be multiplied by 100 and expressed in%. H_UIs the total heat of reaction obtained by differential thermal scanning analysis at a constant temperature_TIs the heat of reaction obtained by differential thermal scanning analysis with isothermal heating, and dQ_T/ Dt is the heat generation rate. Here, the isothermal reaction rate dβ / dt is defined below.
[0032]
dβ / dt = (1 / H_T) · DQ / dt)_T
dβ / dt is expressed by the following equation as a function of the temperature T (K) and β.
dβ / dt = (k₁+ K₂β^m) ・ (1-β)ⁿ
k₁= A₁exp (-E₁/ RT)
k₂= A₂exp (-E₁/ RT)
Where A₁, A₂, E₁, E₂, M, and n are constants, and R is a gas constant. β is determined from the differential equation regarding β, dβ / dt is determined, the curing speed dα / dt is determined based on dβ / dt, and the curing degree α is determined by integrating the curing speed.
[0033]
As the optical fiber strain sensor 15, the following sensor (1) or (2) can be suitably used.
(1) EFPI-FOSSII-04-PE (manufactured by Fiber & Sensor Technologies)
(2) FOS-50003-N (manufactured by FISO Technologies)
These are all EFPI (Extrinsic Fabry-Perot Interferometer, extrinsic Fabry-Perot interferometer), in which an input / output side optical fiber and a reflection side fiber are fixed and mounted on the instrument body, and between the two fibers. Is provided with an air gap, the opposite end faces of both fibers are formed in a parallel plane to form a Fabry-Perot interferometer, and the strain is measured based on the amount of interference light or the fluctuation of the peak wavelength due to the fluctuation of the gap interval. It is a well-known high-performance and high-precision measuring instrument.
[0034]
The degree of cure can be measured directly by a dielectric sensor. The dielectric sensor is a well-known measuring device that measures the ion viscosity corresponding to the degree of cure. The dielectric sensor measures the phase shift and the amplitude of the electrical sensor response corresponding to the electric polarization caused by the curing, and based on the phase shift and the amplitude, the relative permittivity ε (= ε′−iε ”). ) Is determined as the imaginary part of), and ε ″ = ρ / (ω · ε₀) Is measured (= (1 / ρ) .ohm cm) determined by the relational expression Where ρ is the ionic conductivity, ω is the angular velocity of the applied electric field, ε₀Is the dielectric constant in vacuum. The degree of cure can be corrected by an optical fiber strain sensor. The inventors measured the change in specific volume during the curing process using a specific thermosetting resin, derived an equation that describes the specific volume as a function of temperature and the degree of cure, and reached a constant value for the degree of cure. It was found that the curing shrinkage ended at the time when the curing was performed and the specific volume became constant when the curing temperature was in a region where the curing temperature was kept constant. This point is detected by the optical fiber strain sensor. The degree of cure at this point is uniquely determined depending on the temperature, and the degree of cure at this point can be accurately calculated.
[0035]
The embodiment of the intelligent molding method for a thermosetting resin-based composite material according to the present invention is performed by the following steps.
Step 1:
A thermometer, particularly two thermometers, a first thermometer 13 and a second thermometer 14, are arranged at a plurality of locations on the object to be molded, and the temperature Tb and the temperature Tc are measured. Further, it is preferable that the optical fiber strain sensor 15 is arranged and the strain is measured.
[0036]
Step 2:
The set temperature T (t) as a function of time is ideally set in the calculator 7. The ideal setting of the temperature is known from past case studies or theoretical analysis, and it has been found that, in particular, a sudden rise in temperature due to heat generation of the curing reaction has an adverse effect.
[0037]
Step S3:
The curing degree α is calculated in real time based on the curing reaction rate equation (3) programmed in the calculator 7. Alternatively, the degree of cure is empirically obtained from past cases, and is known as a function of temperature and time, and the degree of cure α is tabulated as a value corresponding to temperature and time. Calculator 7 has such a table. The degree of cure α can also be measured directly by a dielectric sensor. The curing speed is determined from the degree of curing. The value of the curing degree α can be corrected by an optical fiber strain sensor.
[0038]
Step S4:
The temperature difference (Tb−Tc) is obtained by the calculator 7. The two parameters ht / A and B / A are calculated by the calculator 7 by the simultaneous equations (1) or (2) based on the measured values at a plurality of times, and are determined with high accuracy. In equation (2), α has already been obtained, and r (Tc, α) is known.
[0039]
Step S5:
If the overall electric heat coefficient ht and other parameters (the amount of reaction heat Q per unit area / curing speed) are determined by the calculation, a temperature change dTc / dt at an arbitrary time is calculated based on the equation (1). The temperature Tc at an arbitrary time is calculated by integration. By assuming various heating rates for Tb and repeating the calculation, a maximum value Tcmax of Tc depending on the heating rate is obtained.
[0040]
Step S6:
When Tcmax is expected to exceed the maximum allowable temperature of Tc when Tb is raised according to the set temperature cycle, the maximum temperature increase is performed within a range where Tcmax does not exceed the maximum allowable temperature of Tc. The speed is selected, and the set temperature Tb is reset based on the temperature increase speed. Since the heat of curing reaction is incorporated in equation (2), the temperature of the pressurized medium 6 in the pressure vessel 3 corresponds to the predicted temperature calculated by equation (2) in which the heat of curing reaction is incorporated. Is controlled, the temperature Tc can be adjusted to the temperature predicted by the equation (2). In particular, the temperature Tc can be controlled normally so as not to exceed the maximum allowable temperature. Thereafter, when Tb reaches the set curing temperature (holding temperature), the temperature is kept constant, and thereafter, when the degree of cure α reaches a predetermined value indicating the end point of curing, the temperature is set. The temperature decrease of Tb is started at the temperature increasing rate. Before the curing degree α reaches the value, the value of the curing degree α can be corrected based on the measurement value of the optical fiber strain sensor.
[0041]
Example:
The above-described optical fiber sensor is embedded in 88 plies of carbon fiber / heat-resistant tough epoxy resin prepreg (Mitsubishi Rayon: MR50K / # 982), autoclave-molded, and internal state sensing (curing) during the autoclave molding process Monitoring) was attempted by the present inventors.
[0042]
FIG. 4 shows measured data of a curing process in which the temperature is controlled by the intelligent molding method of a thermosetting resin-based composite material according to the present invention. The horizontal axis indicates minutes, the left vertical axis indicates temperature and degree of cure (%), and the right vertical axis indicates strain. A curve (a) indicated by a dotted line indicates a standard set temperature. The curve (b) shows the measured temperature Tc of the molding target. The curve (c) shows the specific volume calculated from the specific volume calculation formula. Curve (d) shows the degree of curing determined from the curing reaction rate equation. The curve (e) shows the strain measured by the optical fiber strain sensor. The curve (f) indicates the curing shrink end time. The degree of cure eventually approaches 1 (100%).
[0043]
According to the prior art, as shown in FIG. 10 (b), there is a case where the temperature rises suddenly due to the heat generated by the curing reaction, but the intelligent molding method of the thermosetting resin-based composite material according to the present invention. According to FIG. 4, as shown by the curve (b) in FIG. 4, the temperature does not rise higher than the set temperature (a).
[0044]
FIG. 5 shows another embodiment of the method for intelligently molding a thermosetting resin-based composite material according to the present invention. As shown in FIG. 5, if the temperature rise rate of the temperature control (g) of the pressurized medium 6 of the autoclave 3 is set more gently, the control target temperature (b) is set by the influence of the curing reaction heat. Although it may exceed the temperature (a), the degree of the excessive temperature rise is small. According to the method for intelligently molding a thermosetting resin-based composite material according to the present invention, a sharp curing reaction rate (h) as shown in FIG. Can be suppressed.
[0045]
FIG. 4 shows that the curing shrinkage point P exists in a time region where the change of the strain indicated by the curve (e) becomes substantially zero. FIG. 7 is a general graph additionally showing a change curve of specific volume (Specific @ Vol.). After entering a time region in which the properly controlled temperature rise curve does not change, the specific volume curve (h) also enters a state in which it does not change. The point in time at which the specific volume and the strain become constant values substantially coincides with the end point P of curing shrinkage. Curing proceeds further after the end of cure shrinkage. The point Q at which the degree of cure has sufficiently approached 1 (100%) is defined as the end point of the temperature holding step, and the control of the temperature drop is started.
[0046]
FIG. 8 shows a means by which the end point of curing shrinkage can be known more precisely, and shows the specific volume change of the curing process found from the dependence of the specific volume on the temperature and the degree of curing found by the present inventors. I have. FIG. 8 further additionally shows a first-order differential change curve over time (i) of the specific volume and a second-order differential change curve over time (nu) of the specific volume. The second-order differential change curve (nu) exhibits a divergent peak value later than the time point at which the first-order differential change curve (ri) suddenly decreases after maintaining a constant value. The time point at which the peak value is shown coincides with the curing shrinkage end time point Q with high accuracy. After confirming that the first-order differential change curve (i) has entered the non-change state (（) in which it stably maintains zero, the second-order differential change curve (nu) has a peak value going back in time. By searching for a time point having, the end point Q of curing shrinkage can be determined with high accuracy.
[0047]
FIGS. 9A and 9B respectively show a distortion (Strain), a first-order differential change curve (E) of the distortion, and a second-order differential change curve (W) of the distortion. The first and second derivatives of distortion are
dS / dt = {S (t) −S (t−Δt)} / Δt
dS²/ Dt²= {DS (t) / dt-dS (t-Δt) / dt} / Δt
Required by S represents distortion. The case of Δt = 2 minutes is shown in (a), and the case of Δt = 20 minutes is shown in (b). At Δt = 2 minutes, there is no practical correlation with the hardening shrinkage end time point Q, but at Δt = 20 minutes, the first-order differential change curve changes to a non-change state in which it stably maintains zero. After confirming that it has entered, a point in time where the second-order differential change curve has a peak value is searched retrospectively, and a point in time that is further ΔT (20 minutes) from that point is determined as a curing contraction end point Q. be able to. FIGS. 11 and 12 show flowcharts describing the above-described control procedure.
[0048]
【The invention's effect】
The intelligent molding system of the thermosetting resin-based composite material and the intelligent molding method according to the present invention establishes a technique for suppressing an abnormal rise in temperature due to reaction heat and a residual stress due to curing shrinkage without reducing production efficiency. can do.
[Brief description of the drawings]
FIG. 1 is a system block diagram showing an embodiment of an intelligent molding system for a thermosetting resin-based composite material according to the present invention.
FIG. 2 is a sectional view showing a molding apparatus.
FIG. 3 is a sectional view showing a temperature measurement position.
FIG. 4 is a graph showing a relationship between a temperature fluctuation and a degree of curing.
FIG. 5 is a graph showing three temperature fluctuations.
FIG. 6 is a graph showing known temperature fluctuation and curing speed.
FIG. 7 is a graph showing a general relationship between temperature fluctuation and specific volume.
FIG. 8 is a graph showing the correlation between a change in specific volume and the end of curing shrinkage.
FIGS. 9A and 9B are graphs respectively showing the correlation between the strain and the end of curing shrinkage.
FIGS. 10A and 10B are graphs showing a known set temperature and a measured temperature, respectively.
FIG. 11 is a flowchart showing an embodiment of an intelligent molding control procedure according to the present invention.
FIG. 12 is a flowchart showing another embodiment of the intelligent molding control procedure according to the present invention.
[Explanation of symbols]
3. Autoclave
4: Adjuster
6 ... Pressurized medium
7 ... Calculator
9 ... Molding target
13: 1st temperature measuring instrument
15: Second temperature measuring instrument
19: Control value

Claims (12)

With an autoclave,
A calculator,
A controller for controlling the environmental temperature T ₁ of the inside of the autoclave,
A first temperature measuring device for measuring the environmental temperature T _1,
Comprising a second temperature measuring device for measuring the object temperature T ₂ of the molded object formed from a thermosetting resin composite material in said autoclave,
The calculator calculates the heat balance equation:
dT ₂ / dt = P ₁ · (T ₁ -T ₂ ) + P ₂ · r (T ₂ , α)
P ₁ : parameter P ₂ : parameter r: known curing reaction rate α: known parameter of the curing is simultaneously calculated as a plurality of time equations, and the parameters are obtained by calculation, and the current time is calculated based on the equation. An intelligent molding system for a thermosetting resin-based composite material that calculates a subsequent prediction target temperature and outputs a control value for controlling the environmental temperature to the controller based on the prediction target temperature. The intelligent degree of the thermosetting resin-based composite material according to claim 1, wherein the degree of cure α is obtained by integrating the curing reaction rate equation expressing the curing rate dα / dt as a function of temperature and degree of cure α. Molding system. The intelligent molding system for a thermosetting resin-based composite material according to claim 1, wherein the degree of cure α is directly obtained by a measuring instrument that measures the object to be molded. 3. The intelligent molding system for a thermosetting resin-based composite material according to claim 2, wherein the error in the degree of curing is corrected based on a measurement value obtained by a measuring device for measuring the molding object. The intelligent molding system for a thermosetting resin-based composite according to claim 4, wherein the measuring device is an optical fiber strain sensor. 6. The intelligent molding system for a thermosetting resin-based composite according to claim 5, wherein the optical fiber strain sensor is a Fabry-Perot interferometer type. Increasing the ambient temperature in the autoclave;
A step of measuring the ambient temperatures T ₁ in said autoclave,
A step of measuring the object temperature T ₂ of the press-formed in said autoclave,
Determining the degree of cure α by integrating the curing reaction rate equation;
Calculating a prediction target temperature of the forming target after the current time on the basis of the ambient temperatures T ₁ and the target temperature T ₂ and heat balance equations describing the change of the target temperature and a curing degree α of the forming target Steps and
When the maximum value of the predicted target temperature exceeds the allowable maximum temperature, calculate the predicted target temperature when the temperature rise rate is reduced, and under the condition that the maximum value does not exceed the allowable maximum temperature, Searching for a heating rate;
If the maximum value of the prediction target temperature exceeds the allowable maximum temperature, and controlling the controllers the ambient temperatures T ₁ on the basis of the heating rate,
Maintaining the ambient temperature constant when a predetermined curing temperature is reached,
A step of lowering the ambient temperature when the degree of curing α reaches a predetermined value. The heat balance equation in the calculator is:
dT ₂ / dt = P ₁ · (T ₁ -T ₂ ) + P ₂ · r (T ₂ , α)
P ₁ : parameter P ₂ : parameter r: known curing reaction rate α: known curing degree is described,
The step of calculating comprises:
The method according to claim 7, further comprising: calculating a parameter P ₁ and a parameter P ₂ in the equation based on the temperature difference (T ₁ −T ₂ ) by simultaneously establishing the thermal physical differential equation for a plurality of times. An intelligent molding method for thermosetting resin composites. Measuring the distortion of the molding target,
Calculating by the calculator a cure shrinkage completion time corresponding to the time when the change in the strain becomes smaller,
9. The intelligent molding method for a thermosetting resin composite material according to claim 7, further comprising a step of determining an end time of the step of maintaining the fixed temperature based on the completion time of the curing and shrinking. Calculating the first derivative of the distortion with respect to time by the calculator;
Calculating the second derivative with respect to time of the distortion by the calculator.
10. The heat of claim 9, wherein the time of completion of the curing shrinkage is identified as a time at which the first derivative approaches substantially zero and the second derivative reaches a peak in the step of maintaining the autoclave ambient temperature constant. An intelligent molding method for cured resin composites. The intelligent molding method of a thermosetting resin composite according to claim 10, wherein a Fabry-Perot interferometer optical fiber strain sensor is used for measuring the strain. Increasing the ambient temperature in the autoclave;
Maintaining the ambient temperature constant when a predetermined curing temperature is reached,
A step of measuring the ambient temperatures T ₁ in said autoclave,
A step of measuring the object temperature T ₂ of the press-formed in said autoclave,
A step of obtaining a degree of curing α by integrating the curing reaction rate equation;
Measuring the internal strain of the molding target with an optical fiber strain sensor,
Calculating a time first derivative of the internal strain;
Calculating a time second derivative of the internal strain;
In the step of maintaining the autoclave atmosphere temperature constant, searching for a point in time at which the time second derivative reaches a peak value after the time first derivative is stably set to a zero value state,
Identifying the time point as a cure shrink end time point;
Correcting the curing degree α obtained by integrating the curing reaction rate equation with the curing degree corresponding to the curing shrinkage end time,
With the curing degree α corrected in the step as a starting point, a step of calculating the curing degree α by integrating the curing reaction rate equation again,
A step of lowering the ambient temperature when the degree of cure α reaches a predetermined value.

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