经不同熔体处理的罐用铝材的高温拉伸性能试验  

Tensile Properties of Al Sheet at Elevated Temperature for Pressure Can Prepared by Different Melt-treatment Methods

作　　者：傅高升[1] 陈文哲[2] 钱匡武[1] 任立英[1] 

机构地区：[1]福州大学机械工程学院 [2]福建工程学院

出　　处：《特种铸造及有色合金》2007年第6期416-420,共5页Special Casting & Nonferrous Alloys

基　　金：福建省自然科学基金资助项目(E9810003;E0210011)

摘　　要：通过高温拉伸试验,并结合OM、DTA、SEM、EDAX和TEM等分析手段,探讨了经不同熔体处理的压力罐用铝材(简称“铝原块”)的高温拉伸性能和微观组织的变化规律。结果表明,冶金缺陷的存在是铝原块高温塑性难以充分发挥的主要限制因素,并直接影响到铝材断裂破坏的微观过程,是主要的裂纹源;与未处理和常规处理比较,高效熔体处理技术有效地改善和提高了铝原块的冶金质量,使得材料的高温变形较均匀,其高温断裂方式为穿晶微孔聚集型,断口韧窝较深且分布较均匀,显著提高了其高温塑性;经高效熔体处理的铝原块的变形温度应低于500℃,否则会由于晶粒粗大并易产生低熔点共晶物富Fe(Si)杂质相的溶解而显著降低材料的高温塑性变形性能,其合适的变形温度为400～450℃;采用较低品位工业纯铝经高效熔体处理而获得的铝原块,其主要塑性变形性能不低于现产品性能,其用料低品化是可行的。Effects of different melt-treatment methods on tensile properties at elevated temperatures and microstructure of the Al sheet for pressure cans have been investigated by OM(optical microscope),DTA(differential thermal analysis),SEM(scanning electron microscope),EDAX(X-ray energy diffraction analysis) and TEM(transmission electron microscope) based on tensile testing at elevated temperatures.The results show that the existence of metallurgical defects can be responsible for the restraint of high temperature deformability and directly affect the crack propagation in the aluminum sheet as the key crack resource.Compared with the un-treatment and conventional treatment,the high-efficient melt-treatment can remarkably improve the metallurgical quality and uniformity of high temperature deformation,greatly raising the high temperature plasticity due to transgranular micro-pore gathering crack mode.The high temperature plasticity of high-efficient melt-treated aluminum sheet would be greatly deteriorated as a result of the coarsened grain size and creation of Fe(Si) phase with the deformation temperature more than 500 ℃,so the proper deformation temperature should be chosen in the range of 400~450 ℃.The main plastic deformation properties of the aluminum sheet from lower grade commercially pure aluminum after high-efficient melt-treatment can reach or exceed the properties of using materials,which shows the availability of lower grade aluminum raw materials.

关 键 词：铝 熔体处理 高温拉伸 力学性能 微观组织 

分 类 号：TG146.21[一般工业技术—材料科学与工程]