激光焊接新型钴铬合金的力学性能

Mechanical study of laser welded new Co-Cr alloy

背景:新型钴铬合金为一种不含镍和铍等有害成分的齿科合金材料,但关于其激光焊接的研究尚未见报道。目的:分析新型钴铬合金的激光焊接参数,优选激光焊接电压条件。方法:铸造0.5mm×6mm×30mm的新型钴铬合金试件60个,将试件分成6组。1组作为对照组;5组试件从中间断开,进行激光焊接,光斑直径设定为0.6mm,脉冲持续时间10ms,电压分别为220,250,280,310,340V,焊后进行拉伸强度测试,记录拉伸强度和延伸率。结果与结论:激光焊接新型钴铬合金拉伸强度随电压升高而增加。延伸率在电压低于280V时,随电压增大而增加;高于280V时,随电压增大而降低。电压为280V时,激光焊接新型钴铬合金的拉伸强度为(679.94±46.87)MPa,延伸率为(5.91±0.38)%。提示电压280V,脉冲持续时间10ms,光斑直径0.6mm条件下激光焊接新型钴铬合金的拉伸强度和延伸率均能满足临床要求。

BACKGROUND：There are no reports on laser welding about a kind of Co-Cr alloys,which do not include Ni and Be nowadays.OBJECTIVE：To apply laser welding technique to prepare a new Co-Cr alloy in order to provide welding parameters for clinic application.METHODS：Sixty plastic plate patterns（0.5 mm×6 mm×30 mm） were casted from new Co-Cr alloy.All the plates were randomly divided into 6 groups,one as control group,and the others as examination group.The plates of examination group were perpendicularly cut at the center of the plates.After the cut halves were fixed in a jig,they were laser welded using a NG：YAG laser at a several level output energy in increments of 30 V from 220 to 340 V.The spot diameter and pulse duration employed was 0.6 mm and 10 ms.Uncut specimens served as the non-welded control specimens.Tensile testing was conducted and the breaking force was recorded and the data was statistically analyzed.RESULTS AND CONCLUSION：The tensile strength of laser welding New Co-Cr alloys increased with the electric voltage.The elongation increased with the electric voltage at the electric voltage lower than 280 V,but showed contrary trend when the electric voltage higher than 280 V.The tensile strength and elongation was（679.94±46.87） MPa and（5.91±0.38）% respectively at the optimized welding parameters.The tensile strength and elongation of laser welded New Co-Cr alloy under the optimized parameters（280 V,10 ms,spot diameter 0.6 mm） can be satisfied with the clinical requirement.