To improve the mechanical and microstructure properties of low carbon steel (AISI 1020), a thermally annealed biochar (TAB)-aided quenchant was used in this study. The primary goal of this research was to see how effective it was to use a low-cost, thermally conductive (10³S/m) annealed biochar to improve the mechanical and microstructure of a quench hardened steel workpiece as a quenchant. The quenching procedure was carried out in this analysis with pure distilled water and 0.25, 0.5wt% annealed biochar dispersed distilled water nanofluids. The quenched sample with 0.25wt% biochar nanofluid had a faster cooling rate, lower surface roughness, and a higher hardness value from the center to the edges, according to the findings. Similarly, the specific wear rate and coefficient of friction (COF) of 0.25wt% biochar-aided quenchant are 0.0058mm³/Nm and 0.44, respectively. Furthermore, the martensite microstructures in the 0.25wt% biochar nanofluid quenched workpiece are more refined than the distorted martensite in the 0.5wt% biochar nanofluid quenched workpiece. These low-cost, high-performance, and environmental friendly nanofluids made with annealed biochar may be a cheaper alternative to nanofluids made with other high-cost carbon allotropes like carbon nanotubes (CNTs), graphene, and fullerene.

为了改善低碳钢 (AISI 1020) 的机械和微观结构性能，本研究中使用了热退火生物炭 (TAB) 辅助淬火剂。这项研究的主要目标是了解使用低成本、导热 (10 ³S/m) 退火生物炭，以改善作为淬火剂的淬火钢工件的机械和微观结构。在该分析中使用纯蒸馏水和 0.25, 0.5wt% 退火生物炭分散的蒸馏水纳米流体进行淬火程序。研究结果表明，含有 0.25wt% 生物炭纳米流体的淬火样品具有更快的冷却速度、更低的表面粗糙度和更高的从中心到边缘的硬度值。同样，0.25wt%生物炭辅助淬火剂的比磨损率和摩擦系数（COF）为0.0058mm ³/Nm 和 0.44，分别。此外，0.25wt% 生物炭纳米流体淬火工件中的马氏体显微组织比 0.5wt% 生物炭纳米流体淬火工件中的扭曲马氏体更细化。这些由退火生物炭制成的低成本、高性能和环境友好的纳米流体可能是由其他高成本碳同素异形体如碳纳米管 (CNT)、石墨烯和富勒烯制成的纳米流体的更便宜的替代品。