精密成形工程
精密成形工程
정밀성형공정
METAL FORMING TECHNOLOGY
2012年
6期
16-21,60
,共7页
退火%铁素体%珠光体%灰色系统理论%优化
退火%鐵素體%珠光體%灰色繫統理論%優化
퇴화%철소체%주광체%회색계통이론%우화
annealing%ferrite%pearlite%grey system theory%optimization
合理的热处理退火工艺参数匹配是获得均匀、细化微观组织材料的关键。以低碳低合金钢20CrMnTi为研究对象，在临界一亚临界温度Ac附近加热和保温试样，获得细小的片状珠光体和细化的铁素体晶粒。以加热温度和保温时间为设计变量，通过正交试验设计退火工艺方案，获取材料的塑性数据（硬度、屈服强度、断面收缩率和伸长率）。通过多层次分析法计算多目标综合塑性的权重，然后运用灰色系统理论计算退火工艺参数的优化组合，进一步用优化的工艺参数组合退火处理试样。应用扫描电镜测试并优化工艺处理材料的微观组织，获得分布均匀的铁素体和细小片状渗碳体晶粒组织；通过拉伸应力一应变试验曲线分析材料力学性能，均证明该材料的综合塑性明显提高，表明该优化退火工艺参数的方法是正确、可行的。
閤理的熱處理退火工藝參數匹配是穫得均勻、細化微觀組織材料的關鍵。以低碳低閤金鋼20CrMnTi為研究對象，在臨界一亞臨界溫度Ac附近加熱和保溫試樣，穫得細小的片狀珠光體和細化的鐵素體晶粒。以加熱溫度和保溫時間為設計變量，通過正交試驗設計退火工藝方案，穫取材料的塑性數據（硬度、屈服彊度、斷麵收縮率和伸長率）。通過多層次分析法計算多目標綜閤塑性的權重，然後運用灰色繫統理論計算退火工藝參數的優化組閤，進一步用優化的工藝參數組閤退火處理試樣。應用掃描電鏡測試併優化工藝處理材料的微觀組織，穫得分佈均勻的鐵素體和細小片狀滲碳體晶粒組織；通過拉伸應力一應變試驗麯線分析材料力學性能，均證明該材料的綜閤塑性明顯提高，錶明該優化退火工藝參數的方法是正確、可行的。
합리적열처리퇴화공예삼수필배시획득균균、세화미관조직재료적관건。이저탄저합금강20CrMnTi위연구대상，재림계일아림계온도Ac부근가열화보온시양，획득세소적편상주광체화세화적철소체정립。이가열온도화보온시간위설계변량，통과정교시험설계퇴화공예방안，획취재료적소성수거（경도、굴복강도、단면수축솔화신장솔）。통과다층차분석법계산다목표종합소성적권중，연후운용회색계통이론계산퇴화공예삼수적우화조합，진일보용우화적공예삼수조합퇴화처리시양。응용소묘전경측시병우화공예처리재료적미관조직，획득분포균균적철소체화세소편상삼탄체정립조직；통과랍신응력일응변시험곡선분석재료역학성능，균증명해재료적종합소성명현제고，표명해우화퇴화공예삼수적방법시정학、가행적。
A suitable matching of annealing process parameters is the key factor to attain finer microstructure of material. Low carbon low alloy steel (20CrMnTi) was heated near Ac temperature to achieve fine lamellar pearlite and ferrite grains. Annealing temperature and time were used as independent variables, and material property data (hardness, yield strength, e-longation and contraction of cross sectional area) were acquired by orthogonal experiment. The weight of multi-object qualities had been calculated by analytic hierarchy process (AHP), then the optimization process parameters were calculated by the grey theory system. Furthermore, the samples were annealed by optimized parameters. Optimized materials demonstrate that the microstructure is composed of even ferrite grains and the smaller lamellar cementites, and the microstructure morphologies tested by SEM, and mechanical properties by the tensile stress-strain curve show that the material integrated plasticities are ob viously increased by optimizing annealing process. Finally, the new optimizing method is proved to be correct and feasible.
