Next Article in Journal
A Study on Cutting Force of Machining In Situ TiB2 Particle-Reinforced 7050Al Alloy Matrix Composites
Next Article in Special Issue
Physical-Mechanism Exploration of the Low-Cycle Unified Creep-Fatigue Formulation
Previous Article in Journal
Microstructure and Corrosion Behavior of Simulated Welding HAZ of Q315NS Steel in Sulfuric Acid Solution
Previous Article in Special Issue
Experimental Investigation of Thermal Fatigue Die Casting Dies by Using Response Surface Modelling
Article Menu
Issue 6 (June) cover image

Export Article

Open AccessArticle
Metals 2017, 7(6), 193; doi:10.3390/met7060193

Effects of Solution Treatment on Microstructure and High-Cycle Fatigue Properties of 7075 Aluminum Alloy

1
College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China
2
Light Alloy Research Institute, Central South University, Changsha 410083, China
3
School of Mechanical Engineering, Hebei University of Architecture, Zhangjiakou 075051, China
*
Author to whom correspondence should be addressed.
Academic Editor: Filippo Berto
Received: 28 March 2017 / Revised: 19 May 2017 / Accepted: 22 May 2017 / Published: 26 May 2017
(This article belongs to the Special Issue Fatigue Damage)
View Full-Text   |   Download PDF [27125 KB, uploaded 27 May 2017]   |  

Abstract

This research mainly focused on the effects of solution treatment on high-cycle fatigue properties, microstructure evolution, and fatigue fracture morphology of the high strength aluminum alloy (7075 aluminum alloy). The S-N curves and fatigue performance parameters of the alloy were obtained. We found that longer solution treatment time significantly influences the high-cycle (N ≥ 105) fatigue properties of the Al-Zn-Mg-Cu alloy. Under the loading stress of 240 MPa, and the solution treatment of 2 h compared to 1.5 h, 1 h, and 0.5 h, the fatigue life was respectively improved by about 95.7%, 149%, and 359%. The microstructure observations conducted with a scanning electron microscope (SEM) and transmission electron microscope (TEM) are as follows: recrystallization occurs in the grains of the 7075 aluminum alloy under solution treatment, and the grains become large with the length of the solution treatment time. Cracks mainly initiate from the undissolved large phases, and prolonging the solution time can effectively promote the dissolution of the T phase and S phase, decrease the number of dislocations, and lower the rate of the initiation of fatigue cracks at the undissolved large phases due to dislocation glide and dislocation pile-up. In the second stage of crack propagation, the secondary cracks reduce the driving force and the rate of crack propagation, promoting the fatigue properties of the 7075 aluminum alloy, which can be verified by the observation result that fatigue striation widths become narrower with longer solution treatment times. View Full-Text
Keywords: 7075 aluminum alloy; solution treatment; high-cycle fatigue property; microstructure 7075 aluminum alloy; solution treatment; high-cycle fatigue property; microstructure
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Liu, C.; Liu, Y.; Ma, L.; Yi, J. Effects of Solution Treatment on Microstructure and High-Cycle Fatigue Properties of 7075 Aluminum Alloy. Metals 2017, 7, 193.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Metals EISSN 2075-4701 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top