摘要:
Greater emphasis has been placed on smoothness of the floating surface for the applications with floating height of 10 nm or less. To obtain a smooth floating surface, it must be polished with diamond abrasive having a mean particle size of 0.1 μm or less, and conventional ceramic sintered body has poor machinability and it is impossible to use the magnetic heads made of this ceramic sintered body at a floating height of 10 nm or less.The ceramic sintered body according to the present invention contains Al2O3 crystal grains, internal TiC crystal grains existing in the Al2O3 crystal grains and external TiC crystal grains other than the internal TiC crystal grains. The Al2O3 crystal grains and the external TiC crystal grains retain stress caused by the difference in thermal expansion coefficient remaining after sintering, so that the Al2O3 crystal grains and the external TiC crystal grains pull each other in the interface therebetween. As a result, when the ceramic sintered body is machined, micro-cracks generated in the interface can easily grow due to the residual stress in addition to the shearing force caused by the machining operation, so that machinability is improved.
摘要翻译:对于浮动高度为10nm或更小的应用,浮动表面的光滑度更加重视。 为了获得平滑的浮动表面,必须用平均粒度为0.1μm以下的金刚石磨料抛光,并且常规的陶瓷烧结体具有差的机械加工性,并且不可能使用由该陶瓷烧结体制成的磁头 浮动高度为10nm以下。 根据本发明的陶瓷烧结体包含存在于Al 2 O 3晶粒中的Al 2 O 3晶粒,存在于内部TiC晶粒和外部TiC晶粒以外的TiC晶粒。 Al 2 O 3晶粒和外部TiC晶粒保持由烧结后剩余的热膨胀系数的差异引起的应力,使得Al 2 O 3晶粒和外部TiC晶粒在其间的界面处相互牵引。 结果,当加工陶瓷烧结体时,除了由机械加工操作引起的剪切力之外,由于残余应力,在界面中产生的微裂纹容易生长,从而提高了切削性。
摘要:
Electrically conducting ceramics having, as a chief crystalline phase, a perovskite crystalline phase containing La, Cr and Mg and further having, in addition to the chief crystalline phase, an oxide phase containing La, wherein when the atomic ratios among the rare earth element, Mg and Cr in said chief crystalline phase are represented by the following formula, R:Mg:Cr=x:y:z wherein R denotes rare earth elements at least part of which being La, the atomic ratios among the rare earth element, Mg and Cr contained in the whole ceramics are represented by the following formula, R:Mg:Cr=(x+u):(y+v):z wherein R, x to z are as defined above, and u and v are the numbers satisfying the following formulas, 0.0001.ltoreq.u/(x+y+z).ltoreq.0.20, 0.01.ltoreq.(y+v)/(x+y+z).ltoreq.0.60, and 0.ltoreq.v. The ceramics is dense, exhibits excellent sintering property at low temperatures, has high electric conductivity, and remains stable in a reducing atmosphere.
摘要翻译:作为主要结晶相的导电陶瓷具有包含La,Cr和Mg的钙钛矿结晶相,并且除主要结晶相外,还含有含有La的氧化物相,其中当稀土元素, 所述主结晶相中的Mg和Cr由下式表示:R:Mg:Cr = x:y:z其中,R表示至少部分为La的稀土元素,稀土元素,Mg 包含在整个陶瓷中的Cr由下式表示:R:Mg:Cr =(x + u):(y + v):z其中R,x至z如上所定义,u和v是 满足以下公式的数字:0.0001 = u /(x + y + z) = 0.20,0.01(其中,y + v)/(x + y + z)≤0.60, = v。 陶瓷致密,在低温下表现出优异的烧结性能,导电性高,在还原气氛中保持稳定。
摘要:
A ceramic sintered body contains Al2O3 crystal grains, internal TiC crystal grains existing in the Al2O3 crystal grains and external TiC crystal grains other than the internal TiC crystal grains. The Al2O3 crystal grains and the external TiC crystal grains retain stress caused by the difference in thermal expansion coefficient remaining after sintering, so that the Al2O3 crystal grains and the external TiC crystal grains pull each other in the interface therebetween. As a result, when the ceramic sintered body is machined, micro-cracks generated in the interface can easily grow due to the residual stress in addition to the shearing force caused by the machining operation, so that machinability is improved.
摘要翻译:陶瓷烧结体包含Al 2 O 3晶粒,存在于Al 2 O 3晶粒中的内部TiC晶粒和外部TiC晶粒以外的TiC晶粒。 Al 2 O 3晶粒和外部TiC晶粒保持由烧结后剩余的热膨胀系数的差异引起的应力,使得Al 2 O 3晶粒和外部TiC晶粒在其间的界面处相互牵引。 结果,当加工陶瓷烧结体时,除了由机械加工操作引起的剪切力之外,由于残余应力,在界面中产生的微裂纹容易生长,从而提高了切削性。
摘要:
An oxygen sensor device consisting a cylindrical tube of a ceramic solid electrolyte having an oxygen ion conducting property, a reference electrode formed on an inner surface of the cylindrical tube, and a measuring electrode formed on an outer surface of the cylindrical tube at a position at least opposed to the reference electrode, wherein a ceramic layer is formed on the outer surface of the cylindrical tube, the ceramic layer having an opening portion for exposing the surface of the measuring electrode and incorporating a heat-generating member therein, the heat-generating member being buried surrounding the opening portion. The oxygen sensor device as a whole has a cylindrical shape relaxing the concentration of thermal stress and exhibiting excellent thermal shock resistance. With the heat-generating member being buried near the sensing portion, the sensing portion is heated up to a predetermined activating temperature within short periods of time exhibiting an excellent sensor response.
摘要:
The present invention is an electrically conducting ceramic having improved electrical conductivity which comprises a perovskite-type composite oxide of a composition represented by the following formula(La.sub.1-x-y A.sub.x B.sub.y).sub.z (Mn.sub.1-u C.sub.u).sub.v O.sub..delta.wherein A represents at least one type of atom selected from the group consisting of Sc, Y, Nd, Yb, Er, Gd, Sm and Dy, B represents at least one type of atom selected from the group consisting of Ba, Sr and Ca, and C represents at least one type of atom selected from the group consisting of Co, Fe, Ni, Ce, Zr, Mg, Al, Sb and Cr, and x, y, z, u, v and .delta. are the numbers that satisfy the following formulas:0.02.ltoreq.x.ltoreq.0.5,0.1.ltoreq.y.ltoreq.0.6,0.90.ltoreq.z.ltoreq.1.05,0.ltoreq.u.ltoreq.0.5,v=1.0, and at a temperature of 1000.degree. C. in the open air,2.97.ltoreq..delta..ltoreq.3.04.A tubular-type fuel cell containing an electroconductive ceramic in accordance with this invention as an air electrode does not deform during operation for long period of time and yields a stabilized output and a planar type fuel cell which is free from peeling of air electrodes or does not decrease its output by the deformation of the cell.