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The high degree of mixing of W and Cu phases in copper tungstates makes them an attractive source for manufacturing W–Cu composite powders. Hydrogen reduction of copper tungstates provides composite W–Cu powder products with a uniform, homogeneous dispersion of the metal phases. This paper presents test results for a variety of solid-phase reactions to synthesize cupric tungstate (CuWO4). Hydrated, dehydrated, and complex oxides of tungsten and copper have been used as solid reactants. With stoichiometric ratios of reactants, synthesis in air at 800 °C produced 96% to 100% conversion to CuWO4. Heterogeneous synthesis of CuWO4 with the participation of three solid phases (S1 + S2 →S3) required the simplest, most inexpensive equipment. The end product properties of synthesized CuWO4 could be controlled by the proper choice of reactants.

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A task group of the JCPDS—International Centre for Diffraction Data (ICDD) was established for the purpose of investigating a methodology which would be applicable for statistical process control monitoring of X-ray powder diffractometers. A procedure for collecting X-ray diffraction data for statistical process control purposes and the incorporation of these data into control charts are presented. The results of this task group show that, through the use of statistical process control methods, noncontrol situations for diffractometers were detected, the causes of these problems were identified, and these problems were corrected and noted on control charts.