吹砂条件对DZ125合金再结晶和蠕变性能的影响

Effect of Sand Blowing Conditions on Recrystallization and Creep Properties of DZ125 Alloy

在不同吹砂条件下对DZ125合金进行吹砂处理,研究了吹砂强度、吹砂介质以及热处理工艺对合金再结晶及蠕变性能的影响。结果表明,在相同的热处理条件及吹砂介质下,合金的再结晶层厚度随吹砂强度的增加而加深。当吹砂介质和吹砂强度相同时,标准热处理态合金的再结晶层最深,其次是固溶态合金,而均匀化处理合金的再结晶层厚度最小。在0.4MPa/1 min条件下,吹湿砂样品的再结晶层最薄,吹干砂样品次之,而吹河砂样品再结晶层最厚。DZ125合金在980℃/235 MPa下蠕变测试结果表明,再结晶的试样的蠕变寿命明显低于未发生再结晶的标准热处理态合金,而不同吹砂强度下DZ125合金的蠕变寿命相当,说明当再结晶层超过某一厚度值后,其在合金中的损伤作用相当。此外,再结晶对壁厚2 mm到4 mm试样的蠕变性能并无明显的影响。

DZ125 alloy was treated with different sand blowing conditions.The effect of sand blowing strength,sand blowing medium and heat treatment regime on recrystallization and creep properties was studied in detail.The results showed that the thickness of recrystallization layer increases with the increase of sand blowing strength under the same heat treatment process and sand blowing medium conditions.Furthermore,the recrystallization layer of standard heat-treated alloy is the thickest,followed by solution-treated alloy,and the recrystallization layer of homogenization-treated alloy is the thinnest under the same conditions of sand blowing medium and strength.Under the condition of 0.4 MPa and 1 min,the recrystallization layer of wet sand is the thinnest,followed by dry sand,and river sand is the thickest.The creep test results of DZ125 alloy at 980℃/235 MPa showed that the creep lives of recrystallized samples are obviously lower than that of standard heat-treated samples without recrystallization,and the creep lives of DZ125 alloy at different sand blowing strengths are similar,which indicates that the damage effect of recrystallization layer is similar when the thickness of recrystallization layer exceeds a certain value.Moreover,the recrystallization have no obvious effect on the creep properties of samples with wall thickness of 2 mm to 4 mm.