Mechanical Properties of Particulate MMC/AISI 304 Friction Joints

The influence of joining parameters (rotational speed, frictional time and pressure) on the notched tensile strength of dissimilar MMC/AISI 304 stainless steel friction joints is investigated. Frictional pressure and rotational speed have a statistically-significant effect on notched tensile strength values. The highest notched tensile strength properties occur in joints produced using a high frictional pressure (120 MPa) since extremely thin transition regions are produced at the joint interface and the area fraction of joint interface fracture in broken notched tensile test specimens is negligible.The average particle diameter and inter-particle spacing decrease markedly in the region immediately adjacent to the bondline. It is suggested that the decrease in particle dimensions results from the combined effects of non-uniform plastic straining during friction welding and due to thermal shock and impaction of alumina particles on the contacting surface of the stainless steel substrate.