多火次热模锻造GH4133A合金晶粒度与组织变化

Grain size and microstructure change of GH4133A during multiple heating hot-die forging

通过热模锻造技术对GH4133A合金分别进行10%和30%的三火镦粗试验,探索了晶粒度随变形火次的变化规律、变形量对变形机制的影响。结果表明:当以10%变形量锻造时,无论是在1080℃还是在1160℃锻造,晶粒都是随火次增大逐步细化的。而以30%变形量锻造时,二火即累计变形60%时晶粒细化效果最显著,三火时晶粒细化效果不及二火。1160℃时细化效果不及1080℃。GH4133A合金在热模低速条件下是以滑移→孪晶→滑移方式或孪晶→滑移→孪晶→滑移方式进行变形的,且变形温度接近锻造温度区间下部时,多火次小变形同样能细化晶粒。

Deformation of 10% and 30% three-heating upset was carried out on GH4133A superalloy by hot-die forging, and the rule that grain size changed with heating numbers and the influence of deformation on its mechanism were studied. The results show that when hot-die forging is carried out with 10% deformation, either at 1080 ℃ or 1160 ℃, the grain size is decreased gradually as heating numbers increasing. And when the deformation is 30%, the grain size gets thinnest up to 60%deformation at the second heating, but it increases at the third heating. The effect of refining grains at 1160 ℃ is not obvious compared with 1080 ℃. GH4133A＇s deformation track is slipping→twin→slipping or twin→slipping→twin→slipping during low speed hot-die forging, and grain refinement is also obtained by multiple heating saddening when deformation temperature is close to the low limit of forging temperature.