Direct Recycling of Cold Work Tool Steel Swarf into New Cutting Disks via Field‐Assisted Sintering

Grinding swarf on the micrometer scale is produced when steel tools are machined to their final shape. The morphology of this swarf is prone to trapping lubricant and grinding medium, such as Al 2 O 3 and SiC. Due to both shape and contamination, the swarf is considered undesirable for direct recycling. However, utilizing a consolidation technique, such as field‐assisted sintering technology/spark plasma sintering (FAST/SPS), a unique composite material can be made from embedding or dissolving ceramic grinding contaminants into the steel matrix. Herein, ceramic‐contaminated D2 steel swarf, dried from lubricant, is sintered into a 120 mm diameter cutting disk. This disk is then capable of removing sandstone when tested in a mock tunneling rig. The work explores the challenges in scaling up FAST/SPS sintering from 20 mm test samples up to full scale, the extent of SiC dissolution during sintering, and the optimization of postsintering heat treatment parameters.