Abstract: A metal powder has a chromium content of at least 90 Ma %, a nanohardness according to EN ISO 14577-1 of ?4 GPa and/or a green strength measured according to ASTM B312-09 of at least 7 MPa at a compression pressure of 550 MPa.

Abstract: A powder or powder granulate includes a chromium content >80 Ma %, which contains 2 to 20 Ma % iron, optionally up to 5 Ma % dopant, and optionally up to 2 Ma % oxygen, wherein the chromium-containing particles at least partially have pores. The powder displays significantly improved compression behavior and allows the production of sintered components having a very homogeneous distribution of the alloy elements.

Abstract: A powder metallurgical component has a chromium content of at least 80% by weight and pores and/or oxide inclusions which are present in the component. The number per unit area of a sum of pores and oxide inclusions at a cut surface through the component in at least one region is at least 10,000 per mm2.

Abstract: A powder or powder granulate includes a chromium content>80 Ma %, which contains 2 to 20 Ma % iron, optionally up to 5 Ma % dopant, and optionally up to 2 Ma % oxygen, wherein the chromium-containing particles at least partially have pores. The powder displays significantly improved compression behavior and allows the production of sintered components having a very homogeneous distribution of the alloy elements.

Abstract: A powder metallurgical component has a chromium content of at least 80% by weight and pores and/or oxide inclusions which are present in the component. The number per unit area of a sum of pores and oxide inclusions at a cut surface through the component in at least one region is at least 10,000 per mm2.

Abstract: A metal powder has a chromium content of at least 90 Ma %, a nanohardness according to EN ISO 14577-1 of ?4 GPa and/or a green strength measured according to ASTM B312-09 of at least 7 MPa at a compression pressure of 550 MPa.

Abstract: A relatively economical process allows producing sintered shaped parts, such as sliding sleeves in motor vehicle transmissions. Open-pored undercut surfaces are formed at an internal toothing by hypocycloid milling of the part prior to its final hardening.

Abstract: A sliding collar has claw internal toothing and teeth projecting from at least one of the end surfaces. The individual teeth have lateral surfaces configured as lateral surfaces of a cone segment or as lateral surfaces of a cone segment and one or more truncated-cone segments. The novel geometry of the lateral surfaces which extend outward from the root circle results in both manufacturing technology and functional advantages over sliding collars with known tooth geometries.

Abstract: A sintered selector or sliding sleeve, or gear shift sleeve, has internal claw toothing. The individual teeth are delimited on their ends with secondary surfaces having ends that extend radially inward and outward from the root circle of the inner tooth surfaces. The novel geometry of the secondary surfaces extending radially outward from the root circle provide advantages in the manufacture of such selector sleeves by powder metallurgy, compared with those having prior art tooth geometries.

Abstract: A relatively economical process allows producing sintered shaped parts, such as sliding sleeves in motor vehicle transmissions. Open-pored undercut surfaces are formed at an internal toothing by hypocycloid milling of the part prior to its final hardening.

Abstract: A sliding collar has claw internal toothing and teeth projecting from at least one of the end surfaces. The individual teeth have lateral surfaces configured as lateral surfaces of a cone segment or as lateral surfaces of a cone segment and one or more truncated-cone segments. The novel geometry of the lateral surfaces which extend outward from the root circle results in both manufacturing technology and functional advantages over sliding collars with known tooth geometries.

Abstract: A sintered selector or sliding sleeve, or gear shift sleeve, has internal claw toothing. The individual teeth are delimited on their ends with secondary surfaces having ends that extend radially inward and outward from the root circle of the inner tooth surfaces. The novel geometry of the secondary surfaces extending radially outward from the root circle provide advantages in the manufacture of such selector sleeves by powder metallurgy, compared with those having prior art tooth geometries.

Abstract: The invention relates to a polycrystalline SiC shaped body, which consists of 96% by weight to 99.5% by weight of hard-material grains having a core/shell structure, 0 to 0.1% by weight free carbon, remainder a partially crystalline binder phase; having the following properties: density at least 99.5% of the theoretical density, dark green coloring of ground sections or polished surfaces through characteristic light absorption in the orange spectral region at 1.8 to 2.2 eV, resistivity of at least 107 ohm·cm, and fracture toughness of at least 4.0 MPa.m½, measured using the bridge method.

Abstract: A ceramic composite material with a density of >90% of the theoretical density based on SiC and carbon, with a silicon carbide content of between 99.9% by weight and 70% by weight and a carbon content of between 0.

Abstract: Dense sintered bodies are provided whicha) comprise from 45 to 99.5 wt % of SiC, the SiC being present in the sintered body as a crystalline first phase, andb) comprise from 0.5 to 55 wt % of a sintering aid, from 0.5 to 30 wt % of which is selected from the group consisting of reaction products of Al.sub.2 O.sub.3 with Y.sub.2 O.sub.3, mixtures of at least one nitrogen-containing aluminum compound with reaction products of Al.sub.2 O.sub.3 with Y.sub.2 O.sub.3, mixtures of at least one rare earth oxide with at least one nitrogen-containing aluminum compound and/or Al.sub.2 O.sub.3, and from 0 to 25 wt % of which is selected from the group of the nitridic silicon compounds, the sintering aid being present in the sintered body as a second phase and optionally further phases, wherein the second phase and optionally the further phases are either amorphous to an extent of more than 10% or are present in amorphous form at the interface to the first phase to a width of at least .gtoreq.5 .ANG.

Abstract: A composite material includes boron carbide and titanium diboride in a volume ratio B.sub.4 C/TiB.sub.2 of from 90:10 to 10:90 parts and a proportion of elemental carbon greater than 2% by weight up to a maximum of 50% by weight, based on the boron carbide content. The composite material has a density greater than 92% TD, a hardness HK 0.1 greater than 2300, a four-point flexural strength greater than 400 MPa and a fracture toughness greater than 3.5 MPa.sqroot.m. The composite material is suitable for producing wear-resistant components or cutting tools.

Abstract: A process for producing shaped bodies of boron carbide, metal diboride and carbon, which includes(a) homogeneously mixing pulverulent boron carbide with at least one pulverulent monocarbide of an element Ti, Zr, Hf, V, Nb and Ta in an amount corresponding to from 2% to 6% by weight of free carbon, based on the total weight of the boron carbide;(b) shaping this mixture into green bodies of a density of at least 50% TD;(c) heating the preformed body thus obtained to from about 1250.degree. C. to 1450.degree. C. with exclusion of oxygen in a sintering furnace and maintaining it within this temperature range for from 10 to 120 minutes; and(d) subsequently sintering the preformed body by heating to from 2100.degree. C. to 2250.degree. C.

Abstract: Composite materials are provided based on titanium diboride and processes for their preparation.The composite materials contain(1) 70 to 98% by volume of titanium diboride,(2) 1 to 15% by volume of Fe.sub.2 B and(3) 1 to 15% by volume of Ti.sub.2 O.sub.3and have the following properties:density at least 93% of the theoretically possible density of the total composite material,hardness (HV10) greater than 1,900,bending fracture strength (measured by the three-point method at room temperature) at least 400 MPa andfracture resistance K.sub.IC (measured with a sharp incipient crack produced by the bridge method) of at least 4.5 MPa.sqroot.m.

Abstract: The invention relates to mixed sintered metal materials based on high-melting borides and nitrides and low-melting iron binder metals having the composition:(1) 40-97% by volume of borides, such as titanium diboride and zirconium diboride;(2) 1-48% by volume of nitrides, such as titanium nitride and zirconium nitride;(3) 0-10% by volume of oxides, such as titanium oxide and zirconium oxide, with the proviso that components (2) and (3) may also be present as oxynitrides such as titanium and zirconium oxynitride; and(4) 2-59% by volume of low-carbon binder metals, such as iron and iron alloys and to processes for preparing the same.