Effect of microwave heat treatment on microstructure and mechanical properties of SLM prepared WC-12Co cemented carbides

doi:10.13251/j.issn.0254-6051.2024.12.002

Abstract

Abstract: Selective laser melting (SLM) technology was used to prepare WC-12Co cemented carbide specimens, and the optimal SLM process parameters were obtained through the analysis of orthogonal test results, and the specimen formed by the optimal process was subjected to microwave heat treatment, and the effect of microwave heat treatment on the microstructure and properties of the SLM-formed WC-12Co cemented carbide was investigated. The results show that the optimal SLM process parameters is laser power of 100 W, scanning speed of 390 mm/s, scanning spacing of 0.06 mm. When the laser energy density is 97 J/mm³, the specimen has the least microscopic defects on the horizontal surface, the highest relative density and Vickers hardness, which are 87.33% and 1421 HV3. The number of microscopic defects on the SLM formed specimen after microwave heat treatment is greatly reduced compared with that before heat treatment, and the mechanical properties of the material are significantly improved, but the average grain size of WC increases. When the microwave heat treatment temperature is 1300 ℃, the holding time is 20 min, and the temperature increase rate is 15 ℃/min, the SLM formed specimen has the best comprehensive mechanical properties, and the Vickers hardness and flexural strength reach the maximum value of 1586 HV3 and 834 MPa, respectively, and the relative density is 97.4%.

Key words: selective laser melting, microwave heat treatment, WC-12Co cemented carbide, microstructure, mechanical properties

CLC Number:

TG156

Ji Wenbin, Cheng Pengxiang, Dai Shijie, Wang Zihao, Wu Runhe. Effect of microwave heat treatment on microstructure and mechanical properties of SLM prepared WC-12Co cemented carbides[J]. Heat Treatment of Metals, 2024, 49(12): 9-19.

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