Structural design and mechanical properties of porous structured diamond abrasive tool by selective laser melting

Abstract

Additive manufacturing is an important and promising way to realize the structural-functional integration of diamond abrasive tools. In the presented study, the porous diamond grinding heads with different pore structure and porosity were designed and fabricated by selective laser melting (SLM). By analyzing the stress distribution of overall structures and pore units, the 50 %-porosity square-pore structure with lowest stress concentration degree was optimized. The porous composite samples had good SLM formability, including good integrity and connectivity of pore units, and the diamond abrasives were evenly distributed and exhibited good retention and protrusion height. The high retention was attributed to the multiple interfacial system composed of carbide layer and solid solution strengthening layer. Compared with other porous samples, the 50 %-porosity square-pore structured sample with frame supporting unit and uniform stress distribution showed high deformation resistance of 430 MPa in yield strength and energy absorption capacity of 56.4 MJ/m3, which well verified the simulation results. The wear and grinding tests showed that the sharpness and self-sharpening ability of porous samples were significantly superior to the full-dense sample, and the grinding ratio increased with the increasing of the porosity.