This paper has studied the interface recombination characteristics of HIP diffusion bonding of cemented carbide to metals such as industrial fineiron. Carbon steels including A3 steel .45# steel and T10 steel. The formation reason and the controlling means of the detrimental interfacial brittle phase (Fe3W3C ) have been expounded.

The influence of different particle sizes of nickel powder on the structure and properties of WC-9%Ni cemented carbide has been investigated. Moreover. harmful effect of the Ni-aggregation on properties of alloys is discussed.

A series of experiments have been made using the composites of the rare earth oxide and inorganic conmpound as enamel paste suspending agent to replace the clay fully or mostly. This technology had succeeded and obtained industrial use.

W-Ni-Cu Tungsten alloys can be produced by the thermal decomposition-reduction of the W powder mixture with Ni(NO3)2, CuCl2solutions or with Ni(CH3COO)2, Cu(CH3COO)2 solutions. Both manufactured alloys are available for use. The characteristics and problems of the processes using two different mixtures were studied in details. It was clearly shown that the use of the first mixture during reduction results in a lot of toxic gases, which are harm to the environment, and the second mixture is favourable for environment protect and product quality during reduction.

The ore properties of rare earth (RE) ore of Southwest Territory, China, and its beneficiation technology have been studied. The ore is strongly weathered to produce 20% black slime. RE available for commercial use in ore is occurred in two phases: mineral and colloidal. The main (>96%) RE mineral of mineral phase is bastnaesite. The bastnaesite concentrates (30%、 50% and 60% REO) can be obtained by gravity separation or gravity-flotation combined process at 65% recovery of RE. RE minerals of colloidal phase is absorbed in non-crystal minerals of Fe-Mn oxide. It can be recovered by hot HC1 leaching-purification with liquid ammonia-oxalic acid precipitation route at 74.3% of RE, and lead can be obtained as byproduct. The ore and the black weathered minerals are rich in cerium family RE (∑CeO2>90%, CeO2>La2O3>Nd2O3).

The application of new phosphoric extractant Cyanex 272 to the liquid-membrane separation. preconcentrating and extraction of metal ions is described. Comments are made on the present study.

The concept of comented carbide products with unhomogeneous structure. and their applications and developments have been introduced.

Present paper briefly describes the properties of RE superconducting materials. forming process、 research and development, gives the achievements in Hunan RE superconducting materials aid some suggestions for their development.

In present paper. the recent development of photometric analysis of molybdenum in metal and alloy is described.

稀散金属近况（Ⅲ）周令治，邹家炎（广州有色金属研究院广州５１０６５１）３．２ＳＭ的科技进展３．２．１ＳＭ的选矿基本空白，这与ＳＭ多是伴生在其它矿中的性质相关。除了五十年代纳米比亚将合Ｇｅ０．ｏ１５％的锗石，通过磨－浮－精选而获得含Ｇｅ０．３８６％、回...