STUDY OF EFFECTS OF CRYOGENIC TREATMENT ON CASTED AZ80 Mg ALLOY

Abstract

The Mg & its Alloys are considered to be ‘the green engineering materials of the 21st Century. Mg Alloys are light weight , ease of casting and has superior machinability. It has low density, favorable thermal conductivity , specific Strength and Stiffness .AZ80 Mg alloy rectangular Block made by Casting and the effects of various Cryogenic Treatment Such as Rapid Cooling and Rapid Heating etc. on Microstructure and Mechanical Properties has Investigated .Mechanical properties Such as Tensile Strength and Hardness has been Studied. It Shows higher Values of Tensile Strength and Hardness during Rapid Cooling and Rapid heating [RCRH] Cryogenic Treatment Process. Cryotreated AZ80 Mg alloy Shows 8% increase in tensile Strength compared to Untreated condition. Rapid Cooling and Rapid heat Treatment of Mg Alloy was done by heating to 200ºC and then cooling to room temperature and kept for 24 hours for aging and then cool to Liquid Nitrogen Temperature. RCRH Cryogenic Treatment Process Shows 30% increase in tensile Strength Compared to Untreated Condition. The Improvement of the mechanical properties of Mg Alloy with Cryogenic Treatment is attributed to the Synergistic effects of the refine grains, twins precipitates and non- basal slip.