楊合 孫志超 陳康華
摘要:針對(duì)大型復(fù)雜構(gòu)件整體局部塑變成形與晶體缺陷組態(tài)調(diào)控的關(guān)鍵科學(xué)問(wèn)題,開(kāi)展了深入的研究,研究的主要?jiǎng)?chuàng)新如下: 1)揭示了TA15鈦合金局部加載多道次宏觀不均勻變形模式和規(guī)律,探明了局部加載方式等因素與不均勻變形協(xié)調(diào)及成形缺陷的關(guān)聯(lián)關(guān)系,提出了控制成形缺陷的方法;揭示了TA15鈦合金等溫多道次變形行為和組織演變機(jī)理、片層組織動(dòng)/靜態(tài)球化機(jī)制與規(guī)律,建立了球化動(dòng)力學(xué)模型;發(fā)明了模擬鈦合金復(fù)雜大件成形過(guò)程過(guò)渡區(qū)微觀組織演化的物理方法,獲得了等溫局部加載下TA15鈦合金不均勻變形加載道次、冷卻方式、熱處理對(duì)加載區(qū)與過(guò)渡區(qū)微觀組織演化影響機(jī)制;建立了預(yù)測(cè)鈦合金宏觀變形響應(yīng)與微觀組織演化的內(nèi)變量模型、不均勻變形微觀機(jī)理與織構(gòu)演化的微觀相組分模型和微觀組織形態(tài)演化的元胞機(jī)模型。上述成果為鈦合金復(fù)雜大件局部加載成形過(guò)程優(yōu)化控制提供了理論和技術(shù)基礎(chǔ)。 2)揭示了7085鋁合金熱變形行為和再結(jié)晶的影響規(guī)律,建立了不同熱處理狀態(tài)7085鋁合金的本構(gòu)方程及熱加工圖;揭示了成形參數(shù)對(duì)7085鋁合金變形和固溶再結(jié)晶的影響規(guī)律,建立了合金變形-固溶再結(jié)晶圖、再結(jié)晶模型,確定了不發(fā)生變形和固溶再結(jié)晶的形變-固溶回復(fù)區(qū),提出可以抑制再結(jié)晶的拔長(zhǎng)-退火-再拔長(zhǎng)準(zhǔn)等溫工藝,可提高強(qiáng)度、塑性、斷裂韌性和耐蝕性;建立了7085鋁合金多向自由鍛、等溫模鍛成形仿真系統(tǒng)和實(shí)驗(yàn)平臺(tái)。該工作為鋁合金復(fù)雜構(gòu)件整體成形提供依據(jù)。
關(guān)鍵詞:大型復(fù)雜構(gòu)件;整體;局部加載;不均勻變形;微觀組織
Abstract:Conducting in-depth research for the key scientific problems of integral/local plastic forming and crystal defect configuration control for large complex components. Completing research content of first two years and achieving research target with part of excess. Main innovations are as follows: 1) Revealing the unequal deformation rule of TA15 Ti-alloy under multi-pass local loading, uncovering relationships between local loading modes with unequal deformation coordination and forming defects, inventing a method for forming defects control. Revealing multi-pass isothermal deformation behavior and microstructur evolution mechanism of TA15, dynamic/static spheroidizing mechanism and law of lamellar structure, establishing spheroidizing dynamics model. Putting forward a physical method to simulate microstructure evolution of transitional zone, obtaining the affacting mechanism of loading pass, cooling, and heat treatment on the microstructure evolution of loading/transitional zones. Establishing Internal-state-variable model, microscopic phase component model, and cellular automata model. The results provide a theoretical and technical basis for forming process optimization and control of Ti-alloy large complex component. 2) Revealing the hot deformation behavior and the recrystallization law of AA7085 al-alloy, developing constitutive equations and hot working diagrams. Revealing the effects of forming parameters on the deformation and solid solution recrystallization of AA7085, establishing deformation-solid solution recrystallization diagram and model. Determining the deformation-solid solution area within it no deformation/solid solution recrystallization occurring. Putting forward a puling-annealing-pulling quasi isothermal process to inhibit recrystallization, which can improve the strength, plasticity, fracture toughness and corrosion resistance. Developing simulation system and experimental platform for AA7085 multidirectional free forging and isothermal forging. 13 invention patents were applied and 5 have been obtained. won one National Science & Technology Progress Award (second class) in 2011. 61 academic papers were published including 28 indexed by SCI, 1 in the TOP1 journal of international forming manufacturing field, IJP (IF > 5), 2 in Science China, 1 Cover Story in Materials China, 12 in MSE/JMPT/CMS (IF >1), 6 of IF > 2, 9 invited presentations in conferences. Cultivating 32graduate students (12 PhD students, 20 Master), 20 graduated.
Keywords:large complex components; integral; localloading; unequal deformation; microstructure