文档介绍：华中科技大学
硕士学位论文
SAE9310钢电子束焊接工艺及接头组织性能研究
姓名:覃巍
申请学位级别:硕士
专业:材料加工工程
指导教师:王亚军;王春明
2011-01-15
摘要
SAE9310 钢是一种综合性能良好的渗碳轴承钢,目前国内关于此类钢号的焊接
性及接头组织性能研究较少。电子束焊接具有能量密度高、焊缝深宽比大、保护环
境好等诸多优点,是精密焊接此类钢种的最佳选择,研究 SAE9310 钢电子束焊接工
艺及接头组织性能具有重要理论意义和应用价值。
本文对 SAE9310 钢的电子束焊接技术进行研究。通过工艺试验分析了各焊接参
数对 SAE9310 钢焊缝成形的影响。通过室温拉伸、室温冲击、显微硬度、金相、扫
描电镜等分析手段综合评价了焊接接头力学性能及组织特征,在此基础上设计并制
造材料为 SAE9310 钢的尾桨齿轮轴模拟件,进行电子束焊接试验验证。
实验研究结果表明:SAE9310 钢焊接性良好,当选择合适焊接工艺参数时,可
获得成形良好的焊接接头。焊接接头抗拉强度与母材等强,拉伸试样断裂方式为微
孔聚集型断裂,属于典型的韧性断裂;焊接接头具有较高的冲击韧性,冲击试样断
口整体呈现出韧窝+准解理断裂特征,以韧性断裂为主,在裂纹扩展阶段发生脆性断
裂。焊缝及热影响区显微硬度均高于母材。焊缝组织主要为细小板条马氏体,夹杂
了少量残余奥氏体,熔合区附近以柱状晶和树枝晶为主,焊缝中心区域为等轴晶。
SAE9310 钢电子束焊接接头横向残余应力拟合呈正弦分布,为拉应力;纵向残余应
力拟合呈直线逐步递减分布,焊缝附近纵向残余应力为拉应力,远离焊缝处为压应
力。
本文最后设计并制造尾桨齿轮轴模拟件,采用电子束焊接进行验证。试验结果表
明电子束焊缝成形良好,无明显焊接缺陷;焊缝窄且平行、深宽比大;焊接接头应
力变形小,组织性能达到预期效果。

关键词:电子束焊接;SAE9310 钢;焊接工艺;力学性能;组织特征

I
Abstract
SAE9310 steel is a low-cost and good overall performance carburizing bearing steel
which is widely used abroad. Until now, there are no published reports on the welding and
properties of joints of such steel. The electron beam welding, with high energy density,
weld depth to width ratio, better protection of the environment and many other advantages,
is the best choice of a precision welding for such steel. Therefore, research on electron
beam welding and joints properties of SAE9310 steel has important significance meaning
to production guiding.
Electron beam welding of SAE9310 steel was investigated in this effect on
welding seam formation for SAE9310 steel EB welding parameters is
microstrcture and properties of welding jiont were investigate with
room-temperaturetensile test, room-temperature impact test, microhardness test ,
metallographic phase and scanning electron microscopy. The test pieces of SAE9310 steel
material was designed and manufactured, and was welded by the electron beam welding.
The results show that: weldability of SAE9310