摘要:
A sintered ferrite magnet comprises a main phase of an M type Sr ferrite having a hexagonal crystal structure. An amount of Zn is 0.05 to 1.35 mass% in terms of ZnO, the sintered ferrite magnet does not substantially include a rare-earth element (R), and the following Formula (1) is satisfied, where a total amount of Sr, Ba and Ca is M3 in terms of mol, a total amount of Fe, Co, Mn, Zn, Cr and Al is M4 in terms of mol, and an amount of Si is M5 in terms of mol. 0.5 ≦{M3-(M4/12)}/M5≦4.8(1)
摘要:
Provided is a sintered ferrite magnet 10 that contains Sr ferrite having a hexagonal crystal structure, wherein the total amount of Na and K is 0.01 to 0.09% by mass in terms of Na 2 O and K 2 O, an amount of Si is 0.1 to 0.29% by mass in terms of SiO 2 , and the following Expression (1) is satisfied. [In Expression (1), Sr F represents an amount of Sr, on a molar basis, other than Sr which constitutes the Sr ferrite, and Ba, Ca, Na, and K represent amounts of respective elements on a molar basis.]
摘要:
A method for producing a metal fluoride ceramic, comprising: providing a sedimented compound comprising metal fluoride particles having an average particle size lower than 30 nm and a solvent, partially drying the sedimented compound at a temperature lower than 65°C until the partially dried compound comprises from 5 wt% to 45 wt% of the solvent, and sintering, for example in air, the partially dried and sedimented compound. The resulting ceramic is a transparent metal fluoride ceramic having an average grain size lower than 450 nm and having an absorbance lower than 0.05 cm -1 at 1200 nm and lower than 1 cm -1 at 370 nm. Preferably calcium fluoride is used.
摘要:
The present invention relates to an article comprising at least one of a glass or glass-ceramic comprising Al 2 O 3 and at least one of REO or Y 2 O 3 , wherein at least 60 percent by weight of the glass or glass-ceramic collectively comprise the Al 2 O 3 and the at least one of REO or Y 2 O 3 , and wherein the glass or glass-ceramic contains not more than 20 percent by weight SiO 2 and not more than 20 percent by weight B 2 O 3 , based on the total weight of the glass or glass-ceramic.
摘要:
A piezoelectric material contains a first component that is a rhombohedral crystal that is configured to have a complex oxide with a perovskite structure and Curie temperature is set to be Tc1 and a second component that is a crystal other than a rhombohedral crystal that is configured to have a complex oxide with the perovskite structure and Curie temperature is set to be Tc2, in which the absolute value of the difference between Tc1 and Tc2 |Tc1-Tc2| is equal to or lower than 50°C, and a composition near an MPB line is provided in a phase diagram that employs a composition ratio of a first component to a second component for the horizontal axis and temperature for the vertical axis.
摘要:
Procédé d'électrolyse pour la production d'aluminium par réduction d'alumine, dans une cuve comportant une paroi latérale comprenant au moins un bloc latéral, ledit bloc latéral comportant un matériau alumineux présentant - une porosité ouverte inférieure à 10%, et - une composition, en pourcentage massique sur la base du matériau alumineux et pour un total de 100%, telle que : - Al 2 O 3 > 50%, l'alumine bêta représentant moins de 20% de la masse du matériau alumineux, - oxydes moins réductibles que l'alumine à 1000°C : - Na 2 O - autres constituants
摘要:
[Object] To provide a sialon sintered compact having a high hardness and a wear-resistant component made of the sintered compact. [Solution] A sialon sintered compact includes a main phase made of α-sialon, and a sub phase made of β-sialon. The molar concentration of aluminum in the β-sialon is higher than the molar concentration of aluminum in the α-sialon. Such a sialon sintered compact can exhibit high strength. A wear-resistant component made of the sialon sintered compact exhibits a high hardness, and accordingly has high reliability.
摘要:
Synthetic ceramic proppants are described. Proppants having a monodispersity of 3-sigma distribution or lower are also described, including methods to make these proppants and methods of using these proppants.
摘要:
The invention relates to a method of manufacturing porous construction items, such as bricks, ceramic tiles, roof tiles, large-sized wall blocks, pavement items etc. The technical result of the invention is a reduction in energy consumption while preserving the physicochemical properties. The method of manufacturing porous construction items from natural clay raw material that is capable of swelling comprises the preparation of the raw material, moulding, two-stage heating with retention until swelling occurs, and stabilization. Moreover, the first heating stage takes place before the moulding and is carried out simultaneously with the transport of the raw material to the mould filling zone. The moulding takes place in a mould designed as a muffle furnace with a lid, and the second heating stage occurs at a temperature of no less than 1250°C for no less than 10 minutes. Stabilisation occurs in a tilted tunnel furnace, wherein the inside temperature at the entry is no less than 900°C with further cooling of the finished product at a rate of no more than 120 degrees/hour so that the items at the exit are cooled to no more than 30-40°C.