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In order to improve the interfacial bonding between copper and graphite, copper was coated on the graphite by electroless plating. Copper/graphite composites with copper‐coated graphite were fabricated by spark plasma sintering. The effects of copper‐coated graphite on the density, electrical conductivity, mechanical properties, friction and wear properties of copper/graphite composites were studied. The results show that: copper plating on the graphite surface can improve the wettability of graphite and copper, and the interface between them is well bonded. Compared with pure copper, the microstructure of the composites was significantly refined after adding copper‐coated graphite. The mechanical properties of the composites were significantly improved, with yield compressive strength and elastic modulus increasing by 220 % and 240 %, respectively. With the increase of copper‐coated graphite contents, the density and the conductivity of the composites gradually decreased. The friction coefficient and wear rate of the composites were significantly reduced. The friction and wear mechanisms of the composites are mainly oxidation wear, fatigue wear and adhesive wear.

Improving strength without sacrificing toughness is a permanent request for the development of advanced engineering materials. Herein, a novel energy‐saving strategy is developed to obtain strong but tough low‐alloyed steels. A medium‐carbon steel (42CrMo) is used for demonstration. Warm deformation (tempforming) is applied to the hot‐rolled and air‐cooled 42CrMo steel. After tempforming, the microstructure consists of nano‐sized carbides and highly textured ultrafine grains. The tensile strength of the tempformed steels can reach 1.2 GPa, while the impact toughness is higher than 100 J even at temperatures as low as −80 °C, which are one order of magnitude higher than the counterpart steel after tempering. The present work sheds light on the design and fabrication of high‐performance engineering steels with an excellent combination of strength and toughness.