Zeitschrift für Materialwissenschaften und Ingenieurwesen

The Creep Kinetics of Sand Cast Zinc-Based Alloys No. 2, ACuzinc5, and ACuzinc10

Abstract

Mir AA and Murphy S

Compressive creep tests have been carried out on zinc-rich alloys No.2 (Zn-4% Al-2.8% Cu-0.03% Mg), ACuZinc5 (Zn-3% Al-5.2% Cu-0.04% Mg) and ACuZinc10 (Zn-3.5% Al-9.3% Cu-0.03% Mg) in the stress range 20 to 100 MPa and at 70 to 160°C. Along with creep, other properties of ACuZinc alloys are claimed to be better than conventional zinc alloys No.3 and No.5, and ZA alloys. The primary creep contraction was generally found to increase with increasing copper content in a non-linear fashion. The secondary creep rates of No.2 were slightly lower than those of ACuZinc5 and ACuZinc10. Based on the above equation, continuous design stresses were calculated under different testing conditions which showed that both ACuZinc alloys were inferior in creep strength to No.2 due to its lower secondary creep rates. The results and microstructure of alloys also showed that in all three alloys, the creepcontrolling mechanism is the dislocation climb over second-phase (ε) particles.