Nanocoating for High-efficiency Industrial Hydraulic and Tooling Systems

[摘要] Characterization of the AlMgB14-based coatings revealed their semi-crystalline nature; as a single phase, AlMgB₁₄ appears amorphous. Combining this material with TiB2 through comminution of very fine-scale powders (~100 nm), produces a bulk solid that exceeds the hardness of its respective constituent phases. Through physical vapor deposition processing, the resulting nanocomposite coating combines the wear resistance characteristic of hard materials (e.g. the AlMgB₁₄) with a regenerating lubricant. Within the top layers (10-20 nm) of the nanocomposite coating, the same TiB2 phase used to enhance the strength and provide ductility to the otherwise brittle AlMgB₁₄ material reacts with available oxygen to form boron oxide. As the atoms of TiB₂ continue to react, layers of boric acid begin to form at the surface. This affords an exceptionally low coefficient of friction (as low as 0.02) to the coating. Physical vapor deposition processing parameters were evaluated and optimized during the project to minimize the difficulties common to transitioning a laboratory-scale process or technology to a salable product. Coating process times and temperatures, process gas flows and ramp rates, and a number of other adjustable parameters were optimized based on the results of testing and coating characterization. The overriding goal of all of these efforts was a repeatable coating process that yields the benefits observed in the laboratory, independent of the intended product or market.

[发布日期] 2011-06-22

[学科分类] 材料科学（综合）