摘要
钎焊金刚石工具工艺中不当的加热速率与保温时间会导致合金焊粉熔化不完全或者过度流淌,严重影响焊粉与金刚石界面发生的化学冶金结合及其对金刚石产生的包埋与爬升效果。为了探索真空钎焊过程中夹具的材料、几何结构等对金刚石工具半成品温度分布的影响,利用ANSYS仿真软件对镍基焊粉钎焊金刚石工具进行温度场分布特性分析。结果表明:在一定加热工艺条件下,夹具及工件的几何外形对温度分布影响较大,5 mm厚石墨板最佳;厚度大于10 mm工件易出现焊料融化不完全现象;多件工装加工中保温时间须根据工件数量调整。适当条件下更换夹具厚度、大小、形状及调整保温时间,可减小一定的温度影响。根据仿真结果拟合的加热工艺曲线调整工艺,并应用于生产中,能明显减小废品率。
Incomplete melting or excessive flowing alloy powder in vacuum brazing of diamond tool may be accrued by improper heating rate and holding time of brazing process, then chemical and metallurgic bonding between diamond and binder be seriously affected, so as the filler embedding and climb effect on diamond. In order to research the effects of material and geometric structure of fixture on temperature distribution of semi-finished vacuum brazing diamond tools, characteristics of temperature distribution in brazing diamond tools with nickel base filler alloy powder were analyzed by finite element software ANSYS. The results show that, temperature filed is greatly affected by geometric shape of fixture geometry of workpiece under the certain heating process conditions, and graphite plate with 5 mm is the best; filler alloy powder on workpiece thicker than 10 mm is prone to melt incompletely; holding time must be adjusted by number of workpiece. Temperature influence can be reduced by changing fixture and holding time under the appropriate conditions. Rejection rate can reduce significantly with the improved brazing process adjusted by simulation result.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2015年第4期505-512,共8页
Materials Science and Engineering of Powder Metallurgy
基金
南京航空航天大学研究生创新基地(实验室)开放基金(kfjj201432)
中央高校基本科研业务费专项资金资助
江苏省产学研前瞻性联合研究项目(BY2011102,BY2012010,BY2012013,BY2012015,BY2013003-04,BY2013003-14,BY2013003-15)
