变形工艺对GCr15钢在线球化的影响

根据离异共析原理,对GCr15钢采用先促进碳化物析出,再变形破碎的工艺,即分别采用两道次变形工艺和三道次变形工艺在Gleeble-2000型热模拟机进行变形实验,对比不同变形工艺下GCr15钢的显微组织和硬度,分析变形道次、碳化物析出区间冷却起始温度和冷却速度对组织球化的影响。结果表明:三道次变形工艺在实现GCr15钢组织球化和材料软化方面较两道次变形工艺有明显优势;对于GCr15钢,在三道次变形工艺中,把未再结晶区变形温度控制在900℃,并在900～800℃采用1℃/s的冷却速度,能够形成大量的球化组织,材料明显软化,可实现钢大部分组织在线球化。

Effects of Deformation Process on On-line Spheroidizing of GCr15 Steel

The technique of break and deformation after carbide precipitation for GCr15 steel is worked out by DET （divorced eutectoid transformation）. The experimental research of using Gleeble-2000 thermal simulator adopts two passes deformation technology and three passes deformation technology respectively. The effect of deformation passes, initial cooling temperature of carbide precipitation interval and cooling rate on spheroidizing of organization has been studied by comparing microstructure and hardness. The results indicate that three passes deformation is superior in realizing spheroidizing of organization and softening of material to two passes deformation. It could obtain an amount of organization in spheroidizing and soften material in the condition that the deformation temperature in nonrecrystallization zune is 900 ℃ and the cooling rate between 900-800 ℃ is 1 ℃/s in three passes deformation. It could also realize on-line spheroidizing of most organization.