Characteristic of Mechanical and Morphological Properties of Heat Rolled Laterite Steel with Variety of Size Reduction

Abstract

Indonesia has the most laterite ore reserves in the world. The element originated from the laterite ore is one of the materials in the steel industry. Despite its plentiful of reserves, laterite steel ore has not been used to its maximum potential. This research aims to overview reduction effect on mechanical properties of laterite steel as a result of heated rolling process with various reduction. The reduction variety used in this research were 30%, 40%, 50%, and 60%. Also, the temperature was 980oC. As a result of this research, the increment of reduction followed by the increment of hardness and firmness level of laterite steel. It is proofed by hardness and tensile test. Firmness of the material increased as the reduction increases. The most optimized mechanical properties obtained by 50% reduction, the hardness number was 280.03 HB, tensile strength 620 MPa, elongation 32%, yield 493.33 MPa. Micro structures which formed in this process are ferrite and pearlite phase with very fine pellet size and even pearlite distribution. Fracture types are brittle and ductile fracture with very fine pellet size.