Post-Weld Heat Treatment of API 5L X70 High Strength Low Alloy Steel Welds.

High Strength Low Alloy (HSLA) steels are the materials of choice in pipeline construction with the API X70 grade as the steel for the majority of pipeline networks constructed during the late 20th and early this century. This paper reports on the influence of Post-Weld Heat Treatment (PWHT) on the reduction of residual stresses, resulting changes in the microstructure, and mechanical properties of a multi-pass, X70 HSLA steel, weld joints made by a combined Modified Short Arc Welding (MSAW) and Flux Cored Arc Welding (FCAW) processes. Neutron diffraction results highlighted high magnitude of tensile residual stresses, in excess of yield strength of both parent and weld metal, in the as-welded specimen (~650 MPa), which were decreased substantially as a result of applying PWHT (~144 MPa).

Synthesis of BiS thin films based on pulse-plating bismuth nanocrystallines and its photoelectrochemical properties.

The solubility of Bi in aqueous solution is an important factor that limits the fabrication of high-quality BiS thin films. In order to find a low-cost method to manufacture high-quality BiS thin films, we are reporting the preparation of the BiS thin films based on pulse-plating method in this paper for the first time. The nano-bismuth particles were obtained by electroplating on fluorine-doped SnO (FTO)-coated conducting glass substrates with saturated bismuth potassium citrate solution as the electroplating bath, and then it was put into a muffle furnace to oxidize.

Monitor application of multi-electrochemical sensor in extracting bromine from seawater.

In this paper, a set of online measurement devices of multi-electrochemical sensor was investigated. Combined with industrial distributed control system, it was first applied in extracting bromine from seawater to realize the real-time adjustment of production process parameters. In the process of extracting bromine from seawater, the pH value of acidified raw brine, the addition amount of Cl in the oxidation stage and the addition amount of SO in the absorption stage are key parameters to control the whole production process.

Effect of niobium content on the microstructure and Young's modulus of Ti-xNb-7Zr alloys for medical implants.

New generation titanium alloys with low elastic moduli are promising materials for medical implants, particularly load-bearing orthopaedic implants. In this paper, the effect of niobium content on the microstructure and mechanical properties of new Ti alloys including Ti-23Nb-7Zr, Ti-28Nb-7Zr and Ti-33Nb-7Zr (wt%) is studied. Ti-23Nb-7Zr was found to mainly form α΄ and α″- phases, while both the Ti-28Nb-7Zr and Ti-33Nb-7Zr consisted of α″ and β-phases with an increased amount of β-phase in the alloy with 33 wt% of Nb.

Powder Metallurgy Synthesis of Heusler Alloys: Effects of Process Parameters.

NiCoMnSn Heusler alloy was fabricated with elemental powders, using a powder processing route of press and sinter, in place of vacuum induction melting or arc melting route. The effects of process parameters, such as compaction load, sintering time, and temperature, on the transformation characteristics and microstructures of the alloy were investigated. While the effect of compaction pressure was not significant, those of sintering time and temperature are important in causing or annulling martensitic transformation, which is characteristic of Heusler alloys.

Ferromagnetic Shape Memory Heusler Materials: Synthesis, Microstructure Characterization and Magnetostructural Properties.

An overview of the processing, characterization and magnetostructural properties of ferromagnetic NiMnX (X = group IIIA⁻VA elements) Heusler alloys is presented. This type of alloy is multiferroic—exhibits more than one ferroic property—and is hence multifunctional. Examples of how different synthesis procedures influence the magnetostructural characteristics of these alloys are shown.