2018 年 82 巻 4 号 p. 85-88
In order to reduce the weight of metal materials with low cost, composites of metal and plastic were fabricated. IF steel with good formability was used for the metal. Polyethylene (PE) which has high strength and can be deformed later by thermoplasticity was used for the plastic. PE is a crystalline plastic and is well known to have a strong uniaxial orientation. Texture of such crystalline materials affects the mechanical properties. In this study, to clarify the relation between mechanical properties and texture in such composites, IF steel/polyethylene/IF steel laminates were fabricated by warm-rolling at two rolling reductions of 40% and 50%, and strength of the laminates and textures of the constituent layers were investigated in detail. From pole figure measurements, when the rolling reduction is high, PE was oriented not only to the [001]//RD but also to the [100]//ND, resulting in biaxial orientation. Tensile strength of the IF steel layer was about 9 times higher than that of the PE layer, and that of the laminate was almost consistent with the calculated value by the rule of mixture. The IF steel layer with much higher strength showed isotropic tensile strength related to the γ-fiber texture of <111>//ND, although the PE layer showed remarkable in-plane anisotropy resulting from the strong texture. As a result, tensile strength of the laminates was isotropic for both rolling reductions.