The corrosion fatigue properties and fracture characteristics of friction stir welding joints of 7075 aluminum alloys were studied via corrosion fatigue tests, electrochemical measurements, and corrosion fatigue morphology and microstructure observations. The results show that the corrosion fatigue crack of the friction stir welding (FSW) joint of 7075 aluminum alloys originated in the junction zone between the thermomechanically affected zone and the weld nugget zone. The corrosion fatigue life of the joint decreased with increasing stress amplitude, with an S-N curve equation of lgN = 5.845 - 0.014S. Multiple crack sources were observed in the corrosion fatigue fracture. The main crack source originated from the corrosion pits at the interface between the thermomechanically affected zone and the weld nugget zone due to the influence of the coarse microstructure and the large potential difference between both zones. Corrosion morphologies of a rock candy block and an ant nest appeared in the crack propagation zone and the grain boundary of the weld nugget zone. In addition, fatigue speckles and intergranular fractures were observed, as well as brittle fracture characterized by cleavage steps and secondary cracks in the final fracture zone.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7560481 | PMC |
http://dx.doi.org/10.3390/ma13184196 | DOI Listing |
Materials (Basel)
December 2024
College of Mechanical Engineering, Baoji University of Arts and Sciences, Baoji 721016, China.
The surface roughness of hole machining greatly influences the mechanical properties of parts, such as early fatigue failure and corrosion resistance. The boring and trepanning association (BTA) deep hole drilling with axial vibration assistance is a compound machining process of the tool cutting and the guide block extrusion. At the same time, the surface of the hole wall is also ironed by the axial large amplitude and low-frequency vibration of the guide block.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Sustainable Mining Engineering Research Group, Department of Mining, Mechanic, Energetic and Construction Engineering, Higher Technical School of Engineering, University of Huelva, 21007 Huelva, Spain.
This article shows the behavior of the corrosive effect of acid mine water on carbon steel metal alloys. Mining equipment, composed of various steel alloys, is particularly prone to damage from highly acidic water. This corrosion results in material thinning, brittle fractures, fatigue cracks, and ultimately, equipment failure.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
December 2024
School and Hospital of Stomatology, China Medical University, Shenyang, 110001, Liaoning, China.
The medical devices are subjected to dynamic loads and surrounding physiological condition of the bodily fluids, which will impact the degradation behavior of magnesium (Mg) alloy implants. In this work, the corrosion fatigue (CF) and corrosion behaviors of Mg-xGa (x = 1, 1.5, and 2 wt%) alloys in Hank's balanced salt solutions (HBSS) with 1 g/L and 3 g/L glucose are thoroughly studied.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Hunan Tieyuan Civil Engineering Testing Co., Ltd., Changsha 410075, China.
Materials (Basel)
December 2024
School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
High-entropy alloys (HEAs) have drawn substantial attention on account of their outstanding properties. Additive manufacturing (AM), which has emerged as a successful approach for fabricating metallic materials, allows for the production of complex components based on three-dimensional (3D) computer-aided design (CAD) models. This paper reviews the advancements in the AM of HEAs, encompassing a variety of AM techniques, including selective laser melting (SLM), selective laser sintering (SLS), selective electron beam melting (SEBM), directed energy deposition (DED), binder jetting (BJT), direct ink writing (DIW), and additive friction stir deposition (AFSD).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!