Tensile and fatigue properties of a thermomechanically treated 7475 aluminium alloy

• Published in: Journal of materials science Vol. 23; no. 11; pp. 4115 - 4120
• Main Authors: JAHN, M. T, JIN LUO
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.11.1988
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fatigue; Materials science; Mechanical and acoustical properties of condensed matter; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals, semimetals and alloys; Metals. Metallurgy; Physics; Specific materials; Fatigue life; Scanning electron microscopy; Ageing; Fatigue; Tensile property; Aluminium alloy; Substructure; Experimental study; Tensile strength; Fatigue crack; Cold rolling; Aging; Fractography; Crack initiation; Thermomechanical treatment
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/BF01106845

High-purity Al--Zn--Mg alloy was thermomechanically treated. The process included solution treatment, pre-aging, cold-working by rolling and final aging. Pre-aging was carried out at 100 deg C (TAHA1) and room temperature (TAHA2). Experimental results indicated that the TAHA1 process improved the tensile strength significantly, while the TAHA2 process improved the fatigue life more substantially. Fatigue crack initiation sites were examined carefully by scanning electron microscopy. A correlation between fatigue crack initiation, fatigue striation, tearing ridge, dimple distribution and fatigue life was observed. The experimental results are discussed in terms of substructure and are also compared with the tensile and fatigue properties of a thermomechanically treated 7075 Al--Zn--Mg alloy which were previously reported. 12 ref.--AA(UK/US).