基于钎焊涂覆的树脂结合剂金刚石砂轮及性能研究

Research on resin-bonded diamond grinding wheel based on brazing-coated diamond and its performances

利用钎焊方法对单晶RVD和多晶PDGF12种金刚石磨料表面进行涂覆,制备涂覆前后4种磨料的树脂结合剂金刚石砂轮。研究钎焊过程对金刚石磨粒表面形貌和力学性能的影响,并测试不同砂轮加工硬质合金时的磨削性能。结果表明:钎焊涂覆方法可以在金刚石磨料表面有效包覆一层钎料合金涂层,涂层与金刚石磨粒间形成TiC界面结合。与涂覆前磨粒相比,涂覆后RVD磨粒的冲击韧性(TI)值减小了6%,PDGF1磨粒的TI值增大了42%。用钎焊涂覆PDGF1磨料制作的树脂结合剂金刚石砂轮拥有更低的磨削力和更高的磨削比,但用钎焊涂覆RVD磨料制作的树脂结合剂金刚石砂轮的结果则相反。在相同加工参数下,4种砂轮磨削硬质合金的表面形貌相似,其表面粗糙度在0.50~0.68μm。

The surfaces of two kinds of diamond abrasives,the single crystal RVD and the polycrystalline PDGF1,were coated by brazing method,and the resin-bonded diamond grinding wheels were prepared with four kinds of abrasives before and after coating.The effects of brazing process on the surface morphologies and the mechanical properties of diamond abrasives were studied,and the grinding performances of cemented carbide machined by different grinding wheels were tested.The results show that a layer of filler alloy coating can be effectively coated on the surface of diamond abrasives by brazing-coating method,and the TiC interface bonding is formed between the coating and the diamond abrasive particles.Compared with the particles before brazing-coating,the impact toughness(TI)value of the RVD abrasive particles after brazing-coating decreases by 6%,while the TI value of the PDGF1 particles after brazing-coating increases by 42%.The resin-bonded diamond wheel made of brazing-coating PDGF1 abrasives has lower grinding force and higher grinding ratio,but the resin-bonded diamond wheel made by brazing-coating RVD abrasives has the opposite result.Under the same processing parameters,the surface topographies of cemented carbide grinded by four kinds of grinding wheels are similar,and the surface roughnesses are between 0.50μm and 0.68μm.