金刚石结块磨粒排布层间距实验

Investigation on Interlayer Spacing of Grain Layers of Diamond Segments

分析现有磨粒层间距估算方法,采用洛氏金刚石压头对中等硬度花岗石G603直线等深度划擦.通过测量相同划擦深度、不同划擦间距下划擦过程的划擦力,观察划擦后划痕的形貌,综合分析划擦过程材料去除与划擦力和划痕间距的关系,并优选磨粒排布层间距.实验结果表明:磨粒层间距L存在一临界值间距L_s.当L≤L_s时,划擦力随着L的增大而增大,磨粒间工件材料可通过干涉式整体体积破碎去除;当L>L_s时,磨削力趋于稳定,不随L增大而变化,磨粒协同干涉作用消失,磨粒间工件材料无法成片去除.

In this paper, based on the review of the existing methods for estimating abrasive layers interval spacing, Rockwell diamond indenters were used to scratch a medium-hardness granite G603 with equal scratch depth. During scratching, cutting force on workpiece was monitored. After scratching test, the surface of workpiece was observed. The relationship between the material removal mechanisms and scratch force was dis-cussed in regards with different interlayer spacing. The results show that there is a critical spacing Ls. When the interlayer spacing L is less than or equal to Ls , the scratch force increases with the increase of L, and the material adjacent grains is entirely removed by volume-fractured due to the interference of inter-grains; howev -er, when Lis larger than Ls , the scratch force remained constant and the interference of inter-grains disap-peared. As a result, the material can only be removed individually by each grain.