Liu Decheng, Yue Wen, Kang Jiajie, Wang Chengbiao
School of Engineering and Technology, China University of Geosciences (Beijing), Beijing 100084, China.
Beijing Geological and Mineral Exploration and Development Group Co., Ltd., Beijing 100050, China.
Materials (Basel). 2022 Mar 23;15(7):2380. doi: 10.3390/ma15072380.
Due to the high degree of design freedom and rapid prototyping, laser powder bed fusion (L-PBF) presents a great advantage in the super-hard cemented carbide compared with conventional methods. However, optimizing processing parameters to improve the relative density and surface roughness is still a challenge for cemented carbide fabricated by L-PBF. For this, the effect of the remelting strategy on the forming quality of the L-PBF processed cemented carbide was studied in this article, aiming to explore a suitable process window. The surface quality, relative density, microstructure, and microhardness of the cemented carbide parts fabricated under a single melting and remelting strategy were compared. The results showed that the remelting strategy could efficiently improve the specimens' surface quality and relative density. Besides, the cracks were not obviously aggravated, and the WC grains could distribute more homogeneously on the binder matrix under the remelting strategy. Therefore, the microhardness showed an improvement compared to the single melting strategy.
由于高度的设计自由度和快速成型，与传统方法相比，激光粉末床熔融（L-PBF）在超硬硬质合金方面具有很大优势。然而，优化工艺参数以提高相对密度和表面粗糙度对于L-PBF制造的硬质合金来说仍是一项挑战。为此，本文研究了重熔策略对L-PBF加工的硬质合金成型质量的影响，旨在探索合适的工艺窗口。比较了在单次熔化和重熔策略下制造的硬质合金零件的表面质量、相对密度、微观结构和显微硬度。结果表明，重熔策略可有效提高试样的表面质量和相对密度。此外，裂纹没有明显加剧，在重熔策略下WC晶粒在粘结相基体上分布更均匀。因此，与单次熔化策略相比，显微硬度有所提高。
