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Herein, the tribological performance, thermal and compression resistance behavior of polyimide (PI) reinforced by Fe2O3 decorated reduced graphene is systematically investigated. The remarkable synergistic effect of Fe2O3 decorated reduced graphene oxide (RGO) is demonstrated in its PI wear resistance, and PI/RGO/Fe2O3 composites show good thermal stability and much higher compression resistant ability than PI, PI/RGO, and PI/Fe2O3 composites when the filling contents are same. Additionally, the PI/RGO/Fe2O3 composites also exhibited ultra‐wear‐resistant properties under high load condition, and the lowest wear rate is 3.18 × 10−8 mm3N−1 m−1, which is an order of magnitude lower than that of pure PI. The investigation of its tribological mechanism also showed strong synergistic effect and interface force of Fe2O3 decorated RGO, which contribute to its high‐performance friction‐reducing behaviors. These findings give an inside view to Fe2O3 decorated RGO and its polyimide composites, and open an avenue for the graphene oxide (GO) based composite to act as compression wear‐resisting solid fillers and lubricants when polymer composite with excellent compressive, thermal and tribological properties is required.

Microstructure evolution and tensile properties of large dimensional bulk 304 stainless steel after being rolled with different thickness reductions were characterized in detail. The results showed that the steel consisted of nano-submicro-microcrystalline austenite and nanocrystalline ferrite. Submicrocrystalline austenite was broken down with the thickness reduction, when thickness reduction was 70%, all submicrocrystalline were broken down to nanocrocrystalline, and dispersed more uniformly in the microcrystalline austenite phase in the steel, but the grain size of the nanocrystalline austenite increased to 70 nm. Tensile strength increased from 850 MPa to 965 MPa, yield strength increased from 652 MPa to 837 MPa, elongation decreased from 33% to 19%, intergranular corrosion rate decreased from 1.36 g/(m 2 h) to 0.46 g/(m 2 h). Strength and intergranular corrosion properties increased much. When the thickness reduction was 70%, the tensile strength, yield strength, elongation, and intergranular corrosion properties were the best in the reported value of the steel.