Texture and Microstructure Evolution of Ultra-High Purity Cu-0.1Al Alloy under Different Rolling Methods

The microstructure and texture distribution of ultra-high purity Cu-0.1Al alloy target play a key role in the quality of the sputtering film. The Cu-0.1Al alloy sheets were processed by unidirectional (UR) and cross rolling (CR), and X-ray diffraction (XRD), and electron backscatter diffraction (EBSD) technologies were adopted to observe the texture and microstructure evolution. XRD results reveal that the texture types vary greatly in UR and CR due to the change of strain path. As the strain increases to 90%, S texture occupies the most, followed by copper texture in the UR sample, while brass texture dominates the most in the CR sample. Additionally, the orientation density of texture does not increase significantly with the increase of strain but shows a downward trend both in UR and CR modes. EBSD analysis demonstrates that compared with UR, the deformation microstructure in CR is more uniform, and the layer spacing between the deformation bands is smaller, which can reduce the local-region stress concentration. After the completion of recrystallization, the difference in average grain size between the UR and CR-annealed samples is not significant, and the recrystallized grains become much finer with the increase of strain, while more equiaxed grains can be observed in CR-annealed samples.

High- and Ultra-High-Purity Aluminum, a Review on Technical Production Methodologies

Aluminum and aluminum-based alloys have been used for many years. In view of the increase in material purity requirements of advanced technology products, research regarding high-purity aluminum has gained significant attention in recent years. In this review, we seek to describe the fundamental purification principles and the mechanisms of various segregation techniques used to produce high-purity aluminum. Moreover, we aim to provide an overview of high-purity aluminum production, with particular emphasis on: (a) principles on how to produce high-purity aluminum by layer- and suspension-based segregation methods; (b) discussion of various influencing process parameters for each technique, including three-layer electrolysis, vacuum distillation, organic electrolysis, suspension-based segregation, zone melting, Pechiney, Cooled Finger, and directional solidification; as well as (c) investigations of fundamental working principles of various segregation methods and corresponding reported end-purification for the production of HP-Al. Eventually, the end-reported product purity, and advantages and disadvantages of various purification methods and technologies are summarized. By analyzing and comparing the characteristics of different methods, we put forward suggestions for realizing efficient and environmentally friendly production of high-purity aluminum in the future.

The comparison pack carburizing-nitriding SUS 316 with gas type Welding Grade and Ultra High Purity

The paper discusses the comparison of pack carburizing-nitriding SUS 316 with gas Nitrogen. The purpose of this study was to increase the hardness and corrosion resistance of SUS 316. The research used a pack carburizing-nitriding method with gas type Welding Grade (WG) and Ultra High Purity (UHP). The pack carburizing process uses teak wood activated carbon and barium carbonate as a bio-photo catalyst. The specimens were put into a Sealed Steel Container containing teak wood activated carbon, with a depth of 1 cm below the activated carbon's surface. The test material is then heated until it reaches 850 °C and is held for 1 hour in a heating furnace. Furthermore, the nitriding process, the specimen is put into a tightly closed nitrogen tube, then nitrogen gas flows until the pressure reaches 41 bar and is held for 24 hours. They are using Welding Grade (WG) and Ultra High Purity (UHP) gas types. Furthermore, microVickers hardness testing, optical microscope, and Scan Electron Microscope (SEM) were carried out. The results of the study include a. There was an increase in violence by 41.7 % for UHP and WG (17.3 %). b. The formation of nitride compounds and carbon dissipation on the specimen surface in the UHP carburizing-nitriding pack treatment is more than WG. The formation of a nitride layer is indicated by its fine and dense morphology and film bonding to the substrate. The chemical composition affects the diffusivity of nitrogen atoms in modifying the surface layer of the substrate. The higher the nitride compound formed, the smoother the substrate surface. Also, with UHP treatment, the lower the elemental content of Cr makes SUS 316 more resistant to corrosion. So that SUS 316 UHP can be recommended for use as an implant material