A NOVEL 3d TRANSITION-METAL ALCOCRCUTI HIGH-ENTROPY ALLOY

The phase component, microstructure and compressive properties of a novel 3d transition metal high entropy alloy, AlCoCrCuTi, in as-cast and annealed conditions were investigated. The phases of the as-cast AlCoCrCuTi alloy are composed of primary phase AlCo2Ti (L21), eutectic structure {AlCo2Ti (L21)+ Al3Cr7 (BCC)} and interdendritic phase AlCu2Ti (L21). Through annealing, a rosette feature of the as-cast AlCo2Ti + Al3Cr7 eutectic structure is deteriorated due to the lath-like Al3Cr7 changed to finely-divided one. In mechanics performance, the as-cast alloy exhibits a balanced synergy in hardness (593±37 HV) and ultimate strength (745 MPa), while the hardness of the annealed alloy slightly increases to 647±23 HV at the expense of the ultimate strength. Moreover, the alloy either in as-cast or annealed conditions unfortunately display a typically brittle character. The deficiency of elongation might stem from the diversified brittle and hard phases incorporated, such as AlCo2Ti + Al3Cr7.

Experimental study on mechanical properties of laminated steel fiber rubber concrete

In order to research the effect of the steel fiber volume and the rubber powder diameter on the mechanics performance of the layer steel fiber reinforced rubber concrete, the cube compression tests, splitting tensile tests and four-point bending tests are performed on steel fiber reinforced rubber concrete with steel fiber content of 0.5%, 1%, 1.5%, 2%, 2.5% and rubber powder mesh 20, 40, 60. When 40 mesh rubber powder is added and the volume ratio of steel fiber is 1.5%, the compressive strength of laminated steel fiber rubber concrete reaches the peak value. The splitting tensile strength of laminated steel fiber rubber concrete mixed with2.0% steel fiber and mesh 40 rubber powder is the best. The flexural strength of laminated steel fiber rubber concrete mixed with 2.5% steel fiber and mesh 40 rubber powder is highest in this paper.