Recent advances in ageing of 7xxx series aluminum alloys: A physical metallurgy perspective

Dr. Suib is a Board of Trustees Distinguished Professor of Chemistry and received the CT Medal of Science for his work in catalysis, semiconductors and ceramic composites. He received a B. S. degree in chemistry and geology at the State University College of New York at Fredonia. His graduate and postdoctoral training was completed at the University of Illinois at Champaign Urbana. In 1980, Steve joined UConn’s faculty in the Department of Chemistry and served as the head of the department for 10 years. He is a Fellow of the American Chemical Society and the American Institute of Chemists.

Materials by Design

Wear resistance investigation of titanium nitride-based coatings

Transmission electron microscopy investigation of separated nucleation and in-situ nucleation in AA7050 aluminium alloy

Aging behavior and precipitate characterization of a high Zn-containing Al-Zn-Mg-Cu alloy with various tempers

The invention discloses an aluminium alloy material The aluminium alloy material has the following advantages: the aluminium alloy material has excellent strength and damage tolerance performance combination; and the performances of the surface layer, the performances in different depths below the surface layer and the performances among the cores have good uniformity The aluminium alloy material comprises the following basic ingredients: 67-87wt% of Zn, 11-23wt% of Mg, 05-19wt% of Cu and 003-020wt% of Zr, wherein the following conditions need to be simultaneously satisfied: Zn+Mg+Cu is not less than 105 and is not more than 110 by wt%; Zn/Mg+Cu is not less than 53 and is not more than 60 by wt%; Zr+Mn+Sc+Er+Hf is not less than 024-D/4800 and is not more than 024-D/5000 by wt%; D is the diameter of the round semiconscious casting ingots or the thickness of the casting ingots; D is not less than 250mm and is not more than 1000mm; preferably, the alloy contains 75-84wt% of Zn, 165-18wt% of Mg, 07-15wt% of Cu and 003-020wt% of Zr; and the following conditions need to be simultaneously satisfied: Zn+Mg+Cu is not less than 106 and is not more than 108 by wt%; and Zn/Mg+Cu is not less than 55 and is not more than 57 by wt% The invention also relates to a preparation method of the alloy

Aluminium alloy product suitable for manufacturing structures and preparation method

Phase transformation and microstructure evolution of an ultra-high strength Al-Zn-Mg-Cu alloy during homogenization

The present work gives a quantitative study on the nanoscale precipitates in Al-Zn-Mg-Cu alloys with 6 different chemical compositions (all are in peak-aged state), by combining synchrotron-based small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) techniques. Based on the TEM observations, the size, shape, interprecipitate distance, volume fraction and number density of precipitates are extracted from SAXS data through model fitting. The results show that after peak-aging treatment, the average precipitate sizes in different alloys are close to each other, whereas the volume fraction and number density of nanoscale precipitates increase with the increasing content of Zn+Mg+Cu as well as the Zn/Mg ratio. The results also show that the alloy with a higher number density/volume fraction of nano-scale precipitates tends to have a higher mechanical strength. (C) 2015 Elsevier B.V. All rights reserved.

Xiwu Li

Papers

Aging behavior and precipitate characterization of a high Zn-containing Al-Zn-Mg-Cu alloy with various tempers

Aluminium alloy product suitable for manufacturing structures and preparation method

Phase transformation and microstructure evolution of an ultra-high strength Al-Zn-Mg-Cu alloy during homogenization

Quantitative study of nanoscale precipitates in Al–Zn–Mg–Cu alloys with different chemical compositions

Effect of Zn addition on microstructure and mechanical properties of an Al–Mg–Si alloy