Multiple factors influencing high-purity indium electrolytic refining

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were examined.Significant variations in impurity levels concerning gelatin concentration were observed.Both the gelatin and In3+concentration were moderately positively correlated with the Pb content.The Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl concentration.The Bi element content was positively linked to the electrode distance.As the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually declined.Notably,a critical current density of 45 A·m^(-2) was identified in this behavior.

Tribological behavior of ZK60Gd alloy reinforced by SiC particles after precipitation hardening

In this research, the effect of precipitation hardening on the tribological behavior of the ZK60Gd/SiC composite was studied. For this purpose, ZK60Gd alloy containing with 5 and 10 wt% SiC were produced with stir casting method. The microstructure characterization of the samples showed the wide distributions of Mg_(7)Zn_(3) and Gd(Mg_(0.5)Zn_(0.5)) precipitates were formed during casting. The results of hardness measurement after precipitation hardening at different temperatures showed that the hardness peck was obtained at 175 ℃. The wear tests with different loads(10, 40, 60, 90, and 120 N) and velocities(0.1, 0.3, 0.6, and 0.9 m/s) were performed on the as-cast and heat treated sample at 125, 175, and 225 for 12 h. Between the different precipitation hardening conditions, the precipitation hardened samples at 175 ℃ had the highest hardness values and least wear rate. The sample containing 10% reinforcement had the least wear rate between the unreinforced alloy and the composites. The results showed that abrasive, adhesive, delamination, MML, and fatigue wear mechanisms were the dominant wear mechanisms for the composite samples. In contrast, the dominant wear mechanism for the unreinforced samples was abrasive, adhesive,delamination, MML, and plastic deformation.

Review of micro-scale and atomic-scale corrosion mechanisms of second phases in aluminum alloys

Localized corrosion of aluminum(Al)alloys,such as pitting corrosion,intergranular corrosion,and stress corrosion cracking is closely related to the micro-galvanic corrosion between the second phase and the Al matrix.Using high-resolution transmission electron microscopy and first principles calculations,the factors that affect corrosion mechanisms of the second phase in Al alloys at micro-scale and atomic-scale were examined,including the composition and structure of second phase,pH of the environment,stress and adsorption behavior of adsorbates(such as Cl^(−),H_(2)O,OH−and O_(2)^(−).

Review-material degradation assessed by digital image processing:Fundamentals,progresses,and challenges

Material degradation is accompanied by the changes in surface structure,morphology,and composition.These changes can be recorded by a variety of image acquisition devices that export digital images in grayscale or true color to a detector.Information regarding corrosion type and extent can be extracted with image processing methods.This paper provides a comprehensive review of material degradation assessed by digital image processing.Digital image processing systems used to assess material degradation are briefly reviewed,and the algorithms developed to process metallic materials degradation images are described.Physical and electrochemical methods that can be used to support digital image processing results are summarized,and future work that will augment the present methods of evaluating material degradation are discussed.