Precipitation Kinetics of Water-Cooled Copper Mold Al-Mg-Si(-Mn, Zr) Alloy during Aging.

The aging precipitation behavior of 6061 aluminum alloy that underwent iron casting and water-cooled copper casting and 6061 aluminum with Mn and Zr elements added was studied. Firstly, the hardness curves, tensile properties, and fracture morphology of four aging alloys-6061 (iron mold casting), 6061 (water-cooled copper mold casting), 6061-0.15Mn-0.

Preparation and Performance of a Low-Carbon Foam Material of Fly-Ash-Based Foamed Geopolymer for the Goaf Filling.

The treatment of goaf subsidence is important for sustainable development. Geopolymer is a new type of cementing material with excellent mechanical properties, durability, corrosion resistance, and other advantages owing to its unique three-dimensional spatial aggregation structure. Herein, a type of preparation technology of fly-ash-based foamed geopolymer suitable for goaf filling was developed by adding a chemical foaming agent to the matrix of fly-ash-based geopolymer.

Pd-Free Activation Pretreatment for Electroless Ni-P Plating on NiFe₂O₄ Particles.

A Pd-free activation pretreatment process was developed for electroless Ni-P plating on NiFe₂O₄ particles. The main influencing factors, including NiCl₂·6H₂O concentration, pH of electroless bath and temperature, were investigated. Microstructures of the coating layers were characterized by scanning electron microscopy.