Patent classifications
C22C35/00
LOW-COST HIGH-COERCIVITY LACE-RICH NEODYMIUM-IRON-BORON PERMANENT MAGNET, AND PREPARATION METHOD THEREFOR AND USE THEREOF
A low-cost high-coercivity LaCe-rich neodymium-iron-boron permanent magnet, and a preparation method therefor and the use thereof are provided. The permanent magnet is prepared by mixing and sintering an LaCe-free and HRE-free neodymium-iron-boron main phase alloy and an LaCe-M alloy. An LaCe-free main phase alloy and an LaCe-M auxiliary phase alloy are respectively smelted at first, and then, the same are subjected to powder preparation, mixing, pressing, and sintering, thereby avoiding LaCe entering main phase crystal grains. The depth and concentration of HRE diffused into the magnet are effectively improved by using the characteristics of a low melting point and high flowability of an LaCe-rich crystal boundary phase, thereby improving the uniformity of components and structure distribution in the magnet.
Method for producing manganese containing ferroalloy
To produce manganese containing ferroalloy for steel production, an agglomeration mixture is produced which comprises chromite ore concentrate and manganese ore fines with a grain size smaller than 6-9 mm. The mixture is agglomerated to produce green agglomeration products, such as pellets or other types of agglomerates. The green agglomeration products are sintered in a steel belt sintering furnace to produce either sinter or sintered pellets. The sinter or sintered pellets are smelted in a submerged arc furnace to produce manganese and chromium containing ferroalloy. The ferroalloy produced by the method comprises 6.0-35 w-% manganese and 31-54 w-% chromium.
Method of producing workpiece and workpiece thereof
A method of producing a workpiece includes: providing a first powder, with a hardness of the first powder being less than 250 HV, and with a mean particle size of the first powder being less than 20 m; mixing the first powder and a second powder to form a mixed powder, with the mixed powder including carbon, chromium, iron, and elements selected from the group consisting of molybdenum, nickel, copper, niobium, vanadium, tungsten, silicon, cobalt, and manganese; adding a binder and water to the mixed powder; applying a spray drying process to granulate the mixed powder to form a spray-dried powder; applying a dry pressing process to the spray-dried powder to form a green part; applying a debinding process to the green part to form a debound body; and sintering the debound body into a workpiece having a hardness of higher than 250 HV.
Method of producing workpiece and workpiece thereof
A method of producing a workpiece includes: providing a first powder, with a hardness of the first powder being less than 250 HV, and with a mean particle size of the first powder being less than 20 m; mixing the first powder and a second powder to form a mixed powder, with the mixed powder including carbon, chromium, iron, and elements selected from the group consisting of molybdenum, nickel, copper, niobium, vanadium, tungsten, silicon, cobalt, and manganese; adding a binder and water to the mixed powder; applying a spray drying process to granulate the mixed powder to form a spray-dried powder; applying a dry pressing process to the spray-dried powder to form a green part; applying a debinding process to the green part to form a debound body; and sintering the debound body into a workpiece having a hardness of higher than 250 HV.
High strength and corrosion resistant ferrochrome alloy bulk and article comprising the same
A high strength and corrosion resistant ferrochrome alloy bulk is disclosed, which comprises, in weight percent: 30-68% Cr, 1.5-8% Ni, 1.6-6% C, and the balance Fe and incidental impurities, of which a Fe/Ni ratio is in a range from 5 to 10 and a Cr/C ratio is in a range between 10 and 33. Experimental data reveal that, samples of the high strength and corrosion resistant ferrochrome alloy bulk all possess hardness above HV400 and excellent corrosion resistance due to the high content of Cr. As a result, experimental data have proved that the high-strength and corrosion-resistant ferrochrome alloy bulk of the present invention has a significant potential to replace conventional high-strength stainless steels, so as to be widely applied in various industrial fields, e.g., aviation, transportation, marine facility components, chemical equipment and pipe fittings, engine parts, turbine blades, valves, bearings, building materials, and so on.
Method for producing ferroalloy containing nickel
The invention relates to a method for producing a ferroalloy containing nickel. From a fine-grained raw material containing iron and chromium and a fine-grained raw material containing nickel, a mixture is formed with binding agent, the mixture is agglomerated so that first formed objects of desired size are obtained. The objects formed are heat treated in order to strengthen the objects so that the heat treated objects withstand conveyance and loading into a smelter furnace. Further, the objects are smelted under reducing circumstances in order to achieve ferrochromenickel, a ferroalloy of a desired composition containing at least iron, chromium and nickel.
Amorphous steel composites with enhanced strengths, elastic properties and ductilities
Amorphous steel composites with enhanced mechanical properties and related methods for toughening amorphous steel alloys. The composites are formed from monolithic amorphous steel and hard ceramic particulates, which must be embedded in the glass matrix through melting at a temperature above the melting point for the steel but below the melting point for the ceramic. The ceramics may be carbides, nitrides, borides, iron-refractory carbides, or iron-refractory borides. The produced composites may be one of two types, primarily distinguished by the methods for embedding the ceramic particulates in the steel. These methods may be applied to a variety of amorphous steels as well as other non-ferrous amorphous metals, and the resulting composites can be used in various applications and utilizations.
Iron and molybdenum containing agglomerates
Iron and molybdenum containing agglomerates and a process for producing the agglomerates are disclosed. A green agglomerate is produced from mixing an iron containing powder, a molybdenum oxide powder, and a carbonaceous powder. The green agglomerates can be reduced at a temperature in the range of 400-1500 C.
Iron and molybdenum containing agglomerates
Iron and molybdenum containing agglomerates and a process for producing the agglomerates are disclosed. A green agglomerate is produced from mixing an iron containing powder, a molybdenum oxide powder, and a carbonaceous powder. The green agglomerates can be reduced at a temperature in the range of 400-1500 C.
Silicon based alloy, method for the production thereof and use of such alloy
A method for producing a silicon based alloy having between 45 and 95% by weight of Si; max 0.05% by weight of C; 0.01-10% by weight of Al; 0.01-0.3% by weight of Ca; max 0.10% by weight of Ti; 0.5-25% by weight of Mn; 0.005-0.07% by weight of P; 0.001-0.005% by weight of S; the balance being Fe and incidental impurities in the ordinary amount.