Cobalt-chrome-molybdenum (Co-Cr-Mo) alloy possesses outstanding strength, wear, and corrosion resistance and is a good material candidate for making dental and orthopedic implants. Spherical Co-Cr-Mo powder for additive manufacturing is usually costly due to the high-temperature melting processes and low yield of the powder with desirable particle size in the conventional melt-atomization process. A novel process for making spherical Co-Cr-Mo alloy powder through a simple meltless granulation and sintering process is described herein. The results indicate that the compositional segregation problem can be overcome and high-temperature operation avoided. Segregation-free powder was obtained after sintering above 1200°C. The powder was purified during sintering in a hydrogen atmosphere. The hydrogen purification mechanism is discussed with the aid of thermodynamic modeling using HSC Chemistry software. The oxygen content in the final powder can be controlled to < 0.2 wt.% for powder with particle size < 107 µ m. The final powder retained good spherical morphology.
There is an urgent need for efficient and cost-effective adsorbents for the removal of trace hydrogen phosphide (PH 3 ) from the circular hydrogen systems in the polysilicon chemical vapor deposition furnaces. In this study, a straightforward and cost-effective method was used to synthesize a highly efficient adsorbent (Ce x -Cu y /TiO 2 ) for PH 3 removal using TiO 2 as the carrier and CuO as the active substance. Experimental findings demonstrated that optimal Ce doping amounts (n Cu :n Ce = 20:1) markedly enhanced the adsorbent's performance, with an adsorption capacity reaching as high as 149.14 mg g −1 . Material characterization results indicated that Ce positively influenced the uniform dispersion of Cu on the TiO 2 surface, and Ce doping increased the adsorbed oxygen content of the adsorbent, consequently enhancing its oxidation performance. The investigation of the reaction mechanism and causes of adsorbent deactivation revealed that the depletion of active substances (CuO) in the adsorbent and the accumulation of products such as Cu 3 P and phosphates are the primary factors contributing to its deactivation. Furthermore, high-temperature calcination could restore the activity of the adsorbent, indicating its great potential for engineering applications.
危险品化学品经营许可证（带存储）