磨粒真空预钎焊金刚石磨轮的研制及其加工性能分析  

Development and performance evaluation of the abrasive grains vacuum pre-brazed diamond grinding wheel

作　　者：夏斯伟[1] 肖冰[1] 段端志[1] 袁卫[1] 李文杰[1] 

机构地区：[1]南京航空航天大学机电学院,南京210016

出　　处：《金刚石与磨料磨具工程》2014年第2期16-19,24,共5页Diamond & Abrasives Engineering

基　　金：江苏省产学研前瞻性联合研究项目(项目编号:BY2013003–15;BY2011102;BY2012010;BY2012013;BY2012015;BY2013003–04;BY2013003–14)

摘　　要：分别采用Cu-Sn-Ti合金、A合金稀释的Ni-Cr合金对金刚石真空预钎焊处理,将预钎焊磨粒与金属粉末混匀后热压烧结制作节块和磨轮,并进行磨轮对比磨削实验。由抗压强度、冲击韧性实验测试磨粒力学性能,由抗弯强度实验测试节块抗弯强度。由扫描电镜分析磨粒与胎体界面结合效果。结果表明:Cu基预钎焊磨粒预钎焊层分布均匀,力学性能比A-Ni基预钎焊磨粒提高;预钎焊节块抗弯强度高于常规节块;Cu基预钎焊磨粒与胎体结合致密,界面处Ti元素偏聚富集,Fe、Cu元素相互扩散,实现了牢固化学冶金结合;预钎焊磨轮加工性能明显优于常规磨轮,Cu基预钎焊磨轮锋利度比Ni基预钎焊磨轮提高约15%,实现了多层钎焊效果。Metalization of diamond grains are realized under controlled vacuum brazing conditions using Cu-Sn- Ti filler and Ni Cr filler added with A powder respectively. Pre-brazed diamond segments and grinding wheels are fabricated by powder metallurgy sintering process. Comparative grinding experiments on 635^# granite are carried out between pre-brazed wheels and conventional wheels. Mechanical properties of the abrasive grains are evaluated by compressive strength tests and impact toughness tests. Flexural strength of different segments are evaluated by three-point bending strength tests. Interfaces between the pre-brazed diamond grains and matrix metals are analyzed by SEM. Results show that Cu-based pre-brazed diamond, of which pre-brazed metal layer is uniform distributed, thermal damage degree is lower than that of A/Ni-based diamond. Bending strength of pre-brazed diamond segments are higher than the conventional segments. Accumulation of titanium element and interdiffusion of iron ＆ copper elements, result in the high bonding strength at the interface. Machining characteristics of pre-brazed diamond grinding wheels are all better than the conventional ones. Sharpness of Cu-based wheels is 15 % higher than Ni-based wheels, realizing the multilayer brazing effect.

关 键 词：金刚石磨粒 Cu—Sn—Ti合金 Ni—Cr合金 烧结 金刚石磨轮 多层钎焊 

分 类 号：TQ164[化学工程—高温制品工业] TG74[金属学及工艺—刀具与模具]