锆-4合金的激光焊接研究

Laser Beam Welding of Zircaloy-4

研究了Ｚｒ－４合金ＣＯ_２激光焊接时焊缝成形和接头冶金质量的控制方法，分析了其接头组织和性能。研究表明，焊缝和热影响区的组织呈板条状，焊接接头拉伸强度大于４８０ＭＰａ，延伸率超过３０％。并完成了２．５ｍ长核燃料元件盒的激光焊接。

Zircaloy-4 is widely used in the manufacturing of channel box for nuclear reactor due to its good corrosion resistance at high temperature and ability to absorb neutron. In this paper,the methods to control the weld formation and metallurgical quality of joint during laser beam welding of Zr-4 alloy has been investigated,including control of weld formation,derease of the thermal focus effect and prevention from surface oxidization, etc. The microstructure of the weld and heat affected zone is lathing matensite type. The tensile test shows that the laser welded joint has the tensile strength of more than 480MPa and elongation of more than 30%. Finally, 2. sin long fuel channel box used in low temperature nuclear reactor was welded.