摘要:
In a process for production of ultrafine nickel powder, raw material gas having a partial pressure of nickel chloride vapor within a range from 0.2 to 0.7 is fed into a reducing furnace and the nickel chloride vapor is reduced with hydrogen while flowing the raw material gas in this reducing furnace at a space velocity (SV) within a range from 0.02 to 0.07 sec−1.
摘要:
Chlorine gas from a supply nozzle is mixed with the vapor of nickel chloride and the mixed gas is supplied from a supply nozzle into a hydrogen gas atmosphere in a reduction reactor at a reduction temperature of 900 to 1100° C. The volume of chlorine gas to be mixed versus the vapor of nickel chloride is adjusted to a ratio of 0.01 to 0.5 moles per mole of the vapor of nickel chloride. The particle size of the nickel powder can be controlled appropriately, and also, uniformity of particle size, smoothability of surfaces of particles, and sphericity can be improved.
摘要:
A process for production of metallic powder comprising contacting a metallic chloride gas with a reductive gas in a temperature range for a reducing reaction to form a metallic powder and subsequently contacting the metallic powder with an inert gas such as nitrogen gas to cool the powder, wherein the rate of cooling is 30° C. or more for temperatures from the temperature range for the reducing reaction to a temperature of 800°C. or less. The metallic powder is rapidly cooled, which results in suppression of agglomeration of particles in the metallic powder and the growth of secondary particles. Growth of particles of a metallic powder formed in a reduction process into secondary particles through agglomeration after the reduction process is suppressed, and a ultrafine metallic powder having a particle diameter of, for example, 1&mgr;m or less, can be reliably produced.
摘要:
A throw away cutting tool comprising a holder formed with a wedge groove and a throw away insert having a cutting edge at one end thereof and a wedge portion at the other end, the wedge portion being adapted to be clamped in the wedge groove by elasticity of the material of the holder. The holder is at least partly made of cemented carbide for higher rigidity and cutting stability. Also, the radius of curvature at the deep end of the wedge groove is optimized for crack resistance. Further, the angle of the V-ridge on the holder is interrelated to the angle of the V-groove in the insert for more holding stability and crack resistance.
摘要:
This invention relates to a sintered hard metal for cutting tools and having excellent wear resistance, resistance to thermal deformation, mechanical strength and the like. The present invention resides in the fact that the substrate metal consists of a rich content of the B-1 type hard phase and the surface thin layer consists of a rich content of the ordinary tungsten carbide. B-1 type crystal structure contains one or more Group IVa, Va and VIa metals, carbon, nitrogen and, moreover, tungsten. The thin layer structure has the layer of 5 to 200.mu. thickness on the surface thereof.
摘要:
An object of the present invention is to provide a method for production of metallic powder in which aggregation of particles and growth to secondary particle after reducing process of the metallic powder particle can be prevented, to reliably obtain metallic particles containing few coarse particles and to meet requirements of thinner layer and greater number of layers in recent capacitors, and a production device therefor. The present invention includes a reducing process in which metal chloride gas and reducing gas are contacted to continuously reduce the metal chloride, and a cooling process in which a gas containing metallic powder generated in the reducing process is continuously cooled by inert gas. In the cooling process, a vortex flow is generated by blowing out the inert gas from at least one part around the flowing passage of the metallic powder. Furthermore, during the production of the metallic powder, inert gas flow is generated in the vertical direction along the inner wall of the production device (reducing process and cooling process) continuously. Aggregation of the metallic powder and growth of secondary particles can be reduced to reliably obtain metallic powder having uniform particle size containing few coarse particles.
摘要:
Metal chloride vapor and reducing gas are brought into contact to form metallic powder, the metallic powder is washed in carbonic acid aqueous solution, and the metallic powder is classified in a liquid phase. In this way, metallic powder, such as nickel powder, in which the content of chloride components is extremely small and the coarse particle content is small, can be efficiently produced.
摘要:
This invention relates to a hard alloy consisting of a metallic phase and a hard phase having a B1 type crystal structure, and being represented by the following general formula,(M.sub.1a, M.sub.2b, M.sub.3c)(C.sub.1-x-y N.sub.y O.sub.x).sub.zin which M.sub.1 is at least one of Group IVa elements, M.sub.2 is at least one of Group VIa elements, M.sub.3 is at least one of Group Va elements, C is carbon, N is nitrogen, O is oxygen, a, b, c, x and y are respectively atomic ratios satisfying the relations of a+b+c=1, 0.1.ltoreq.(a+c)/a+b+c).ltoreq.0.7 (c can be zero), 0.05.ltoreq.x.ltoreq.0.5, 0.ltoreq.y.ltoreq.0.5, 0.05.ltoreq.x+y.ltoreq.0.6 and z is an atomic ratio of (C+N+O)/M.sub.1 +M.sub.2 +M.sub.3) satisfying the relation of 0.1.ltoreq.z.ltoreq.0.5.
摘要翻译:本发明涉及由金属相和具有B1型晶体结构的硬相组成的硬质合金,由以下通式表示:(M1a,M2b,M3c)(C1-x-yNyOx)z,其中M1 是Ⅳa族元素中的至少一种,M2是Ⅵa族元素中的至少一种,M3是Va族元素中的至少一种,C是碳,N是氮,O是氧,a,b,c,x和y 分别是满足a + b + c = 1,0.1(=(a + c)/ a + b + c)= 0.7的关系的原子比(c可以为零),0.05 < =0.5,0,0≤y≤0.5,0.05≤x+y≤0.6,z是满足关系为0.1的(C + N + O)/ M1 + M2 + M3的原子比 = z = 0.5。
摘要:
This invention relates to a surface-coated sintered hard body comprising an alloy consisting of at least one of carbides and carbonitrides of Group IVa, Va and VIa transition metals, cemented by at least one of metals and alloys, and two interior and exterior coated layers, the interior layer being a monolayer or multilayer consisting of at least one of carbides, carbonitrides and nitrides of Group IVa, Va and VIa transition metals, in which a part of the non-metallic element or elements are optionally replaced by oxygen, and at least one layer of the interior layer consisting of at least one of carbides, carbonitrides and nitrides of Group IVa, Va and VIa transition metals, in which a part or all of the non-metallic element or elements are replaced by boron, and the exterior layer consisting of at least one of aluminum oxide, zirconium oxide and mixtures or compounds thereof.
摘要:
The present invention relates to a hard cemented carbonitride alloy for cutting tools, which comprises 97 to 75% by weight of a hard phase and 3 to 25% by weight of a binder metal, the hard phase consisting of metallic components of titanium as a main component, 5 to 40% by weight of one or more of tungsten and molybdenum and 3 to 40% by weight of tantalum and non-metallic components of carbon and nitrogen, the proportion of nitrogen being 5 to 40% by weight of the non-metallic components and the binder metal being at least one element selected from the group consisting of iron, cobalt and nickel.