均匀化热处理对电弧增材制造GH4169合金组织影响

Effect of Homogenization Heat Treatment on Organization of GH4169 Alloy by Arc Additive Manufacturing

采用电弧增材制造工艺成形GH4169合金,研究了不同均匀化工艺条件对沉积态GH4169合金微观组织的影响。研究结果显示:当均匀化热处理温度为1 120℃时,随着保温时间的延长,沉积态柱状晶逐渐转变为等轴晶,平均晶粒尺寸呈逐渐长大趋势,Laves相体积分数逐渐减小,在保温90 min后,平均晶粒尺寸长大至178.9μm, Laves相完全溶解;当均匀化热处理保温时间为1 h时,随着热处理温度的升高,晶粒平均尺寸逐渐长大,Laves相体积分数逐渐减小,在热处理温度为1 200℃时,Laves相体积分数降低至0.64%,平均晶粒尺寸长大至170.35μm,此时沉积态柱状晶已完全转化为等轴晶。最终确定均匀化热处理参数为:热处理温度1 120℃,保温时间90 min。

The arc additive manufacturing process was used to form GH4169 alloy,and the effects of different homogenization process conditions on the microstructure of GH4169 alloy in the deposited state were investigated.The results show that when the homogenization heat treatment temperature is 1120℃,with the extension of the holding time,the deposited state columnar crystal gradually transforms into equiaxed crystal,the average grain size gradually grows,and the volume fraction of Laves phase gradually decreases,and after 90min of holding time,the average grain size grows to 178.9μm,and the Laves phase completely dissolves.The average grain size grew and the volume fraction of Laves phase decreased with the increase of heating temperature when the holding time of homogenization heat treatment was 1h.At the heating temperature of 1200℃,the volume fraction of Laves phase decreased to 0.64%and the average grain size grew to 170.3μm.At this time,the deposited columnar crystals have been completely transformed into equiaxed crystals.The final homogenization heat treatment parameters were heat treatment temperature 1120°C and holding time 90 min.