异种金属间激光焊接的初步研究

目的:通过对焊件机械强度的测定及熔合区微观结构的分析,探讨口腔常用合金异种金属间激光焊接的可行性。方法:采用钴铬合金、镍铬合金、纯钛进行异种金属间的激光焊接,测定焊件的最大抗拉、抗弯强度,并进行拉伸断口的扫描电镜观察和熔合区的金相分析,探讨激光焊接异种金属的焊接质量及临床应用的可行性。结果:钴铬和镍铬合金异种金属间的激光焊件机械性能较好,钴铬焊丝组和镍铬焊丝组在最大抗拉、抗弯强度上无显著差异(P>0.05)。纯钛与钴铬或者镍铬合金激光熔接接头脆性大,断面可见严重的裂纹和气孔。结论:钴铬合金与镍铬合金异种合金间的激光焊接,不管采用钴铬焊丝或者镍铬焊丝,都可获得良好的焊接接头。纯钛与钴铬合金或者镍铬合金都不能采用激光直接进行熔接

An experimental study on laser-welded dissimilar alloys in dentistry

PURPOSE: This study evaluated the mechanical properties and microstructure of the joints of laser-welded dissimilar alloys usually used in clinical nowadays. METHODS: The dissimilar alloys for Co-Cr alloy,Ni-Cr alloy and pure titanium were laser-welded. The joints were tested for the ultimate tensile strength (UTS) and the ultimate bending strength (UBS). The tensile fracture surfaces were examined by scanning electron microscopy (SEM). Metallurgical analysis was also performed on polished longitudinal sectioned samples. RESULTS: Laser-welded dissimilar alloys between Co-Cr and Ni-Cr alloy can yield satisfactory mechanical properties, and there was no significant difference of UTS and UBS between Co-Cr welding wire group and Ni-Cr welding wire group (P>0.05). The laser-welded joints for dissimilar metal of pure titanium and Co-Cr,pure titanium and Ni-Cr, showed more brittle characteristics and severe defects ( pores and cracks ). CONCLUSIONS: With Co-Cr or Ni-Cr welding wire, the laser-welded dissimilar alloys of Co-Cr alloy and Ni-Cr alloy can yield satisfactory joints. But pure titanium and Co-Cr alloy, pure titanium and Ni-Cr alloy cannot be directly melted together.