| 2Cr13/9Cr18MoV/2Cr13 composite martensitic stainless steel has been prepared by casting-rolling bonding technique. The effect of heat treatment on structure, hardness, tensile properties and bending properties of composite martensitic stainless steel has been studied systemeticly. Experimental results show that the structure of nearby alloy layers of composite steel produced by casting-rolling bonding transits smoothly and exists no evident interface. After quenched and tempered, the structure of inner layer of 9Cr18MoV consists of tempered martensite, granular carbide and residual austenite. Meanwhile, the structure of outer layer of 2Cr13 is composed of coarse tempered martensite. Tempering can significantly improve the toughness of composite plates, the fracture deflection of quenched and tempered samples is higher than that of quenched but untempered samples.After 1050℃, 30min quenching and 200℃, 2h tempering, casting-rolling composite martensitic stainless steel shows excellent mechanical properties. The hardness of 9Cr18MoV and 2Cr13 alloy layer is 585.7HV(54.8 HRC)and 490.0HV (48.8HRC), respectively. The tensile strength of composite plate is 1539Mpa, the elongation is 7.97%, the bending strength is 18047Mpa, the fracture deflection is 51.84 mm, the maximum bending force is 2.41KN and the fracture energy is 96.73J. The tensile strength of composite steel is similar to that of pure 2Cr13 and 9Cr18MoV steel and the elongation of composite steel is close to that of 2Cr13. The bending strength of composite plate is increased by 11.3 and 9.36 times, respectively, compared with the pure 2Cr13 and 9Cr18MoV. While, the fracture deflection of composite plate is 4.47 and 11.78 times higher than that of pure 2Cr13 and 9Cr18MoV, respectively.The tensile and bending fracture of casting-rolling composite martensitic stainless steel reveal typical plastic fracture characteristics. It is indicated that composite plate having excellent plasticity.
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