ELEVATED TEMPERATURE AND VARIED LOAD RESPONSE OF AS41 AT BOLTED JOINT

The effective application of Mg alloys as automotive power train components is continuously challenged by the ability of magnesium to withstand fastener clamp load under service condition. The stiffness of a joint is strongly dependent on the elastic moduli of the members of the bolted joint. As deflections on loaded bolted steel components could be ignored at low and elevated temperature condition that of magnesium alloys cannot be overlooked. In this work bolt load retention experiments are carried out on AS41 between stresses of 40 MPa to 70 MPa and temperature of 125 degrees C to 150 degrees C. A power law creep relationship coded in finite elemental program is used to describe the time dependent stress-strain response of AS41. The parameters in this relationship are obtained by fitting typical compressive creep test results. A comparison of the model and bolt load retention experiments using load cell measuring techniques shows good agreement.