Numerical simulation was made of molybdenum plate rolling process with sinusoidal profile rolls, and the rolling process parameters were optimized by orthogonal tests. Three-dimensional entity models of both the roll and molybdenum plate were created,and the target function of optimization tests was estab- lished i. e. destruction degree of molybdenum plate. The results from orthogonal simulation rolling tests show that the optimal rolling program for producing 4 mm thick molybdenum plate is as follows.break- down rolling heating temperature of 1 200℃ with deformation degree of 37.5%,heating temperature of 1 150℃ with deformation degree of 24% for 1st rolling after 2nd firing,deformation degree of 23% for 2nd rolling after 2nd firing,heating temperature of 1 100℃ with deformation degree of 20% for 1st roiling af- ter 3rd firing,and final plate thickness of 4 mm for 2nd rolling after 3rd firing. Under the above rolling process conditions, the destruction degree of molybdenum plate may be the minimum.

Research is made on the causes of the cup-cone fractures of lanthanum-doped molybdenum wiresduring drawing, based on the observation and analysis of their morphology and hardness. The results show that the residual Fe is an important influence factor leading to the cup-cone fractures of molybdenum wires. The existing form,particle size and the segregation of La2O3 also results in the cup-cone fractures.

The latest development of SiC particle reinforced Al-based composite is reviewed from its prepa- ration technology, performance and application, respectively. The existing problems of the composite are analyzed during development, and its future development trend is pointed out.

《硬质合金》为国家出版基金项目＂有色金属理论与技术前沿丛书＂之一。该项目由国家设立,用于鼓励和支持优秀公益性出版项目,代表我国学术出版的最高水平。本书作者羊建高，材料学博士，国家二级教授，江西理工大学教授、中南大学兼职教授，荣获国务院政府特殊津贴，系中国有色金属工业学术带头人，长期从事钨、钼难熔金属及硬质合金的研究、生产与管理工作。本书在注重基础理论及系统性的基础上，较全面地反映了硬质合金领域中的新成果，包括新工艺、新装备、新产品和新的发展趋势；突出了先进性与适应性相结合，工艺与装备相结合，基本原理与工业实践相结合，资源节约，环境友好等特色。本书内容覆盖晶体结构和相平衡、难熔金属碳化物及粘结金属粉末的生产、硬质合金生产工艺与装备、硬质合金材料、硬质合金的微观结构、硬质合金的性能与检测、硬质合金的应用、硬质合金废料的高效利用、硬质合金生产过程中的防护等，并对相关的科学问题进行了讨论，对加快硬质合金材料科学的发展具有重要的学术价值。

上海洪利净化科技有限公司多年从事高分子精密过滤技术及其各种过滤装置的研发、生产销售及服务,其生产基地即浙江省东瓯过滤机有限公司。我国自主创新的新型过滤技术———刚性高分子精密微孔过滤技术,其研发、生产与销售均由洪利公司完成,此外公司的主打产品还有新型工业层析柱、蒸发器、结晶机、换热器等。

The effects were studied by orthogonal experiments of carbon content, sintering system, cobalt content, ball to raw material ratio, and milling time on volume shrinkage, impact toughness and transverse rupture strength of coarse-grained cemented carbides. The results show that the most important factors af- fecting alloy volume shrinkage are sintering system and milling time,and those affecting impact toughness are sintering system and cobalt content. The most important factor affecting transverse rupture strength is sintering system. By appropriately increasing sintering temperature, milling time and cobalt content, the coarse-grained cemented carbide with better mierostructure and less defects can be obtained, and its relative density,impact toughness and transverse rupture strength are improved.

The surface concave point phenomenon of a sintered cemented carbide product is introduced. In- ternal microstructure of the concave point is observed by scanning electron microscopy （SEM） and the composition of some points are detected by energy spectrum analysis. The results show that the cause of the concave point is resulted from partial mixture with other material near alloy surface.

Experimental study was made of interference effects of the coexisting elements including Mn, As, Cr and Fe on cobalt determination by potentiometric titration. The interference elimination methods are proposed,that is oxidizing low valence Cr （Ⅲ） ,Fe （Ⅱ ） and As （Ⅲ） to high valence Cr（ Ⅵ） ,Fe （Ⅲ） and As （Ⅴ）, and oxidizing Mn （ Ⅱ ） to MnO2 precipitate to be separated and removed. Otherwise, MnOe precip- itate is washed and reduced, and then its cobalt content is determined with flame atomic absorption spec trometry to equalize the measured value by potentiometric titration.

Based on practice and analysis of the general layout and transportation engineering on a molybde- num mine,the proiect layout of various industrial sites and their organic interaction are described. And the key points and experiences for designing the mine are summarized, providing reference for general layout and transportation engineering of the similar mines.

The properties of selenium are introduced, as well as its distribution and resource situation. The extraction-separation methods and application of selenium are expounded emphatically. Meanwhile, the fu-ture development and utilization of selenium resources is pointed out.