The present invention relates to a method of making a cemented carbide comprising mixing in a slurry a first powder fraction and a second powder fraction, subjecting the slurry to milling, drying, pressing and sintering. The first powder fraction is made from cemented carbide scrap recycled using the Zn recovery process, comprising the elements W, C, Co, and at least one or more of Ta, Ti, Nb, Cr, Zr, Hf and Mo, and the second powder fraction comprising virgin raw materials of WC and possibly carbides and/or carbonitrides of one or more of Cr, Zr, W, Ta, Ti, Hf and Nb. The first powder fraction is subjected to a pre-milling step, prior to the step of forming the slurry, to obtain an average grain size of between 0.2 to 1.5 μm.

The cylinder rod of a hydraulic cylinder includes a body portion having a bar shape, and a head portion arranged at a longitudinal end of the body portion. The body portion has a coating formed on its outer peripheral surface. The coating includes, in terms of area ratio in cross section, not less than 56.1% and not more than 84.4% of a chromium carbide phase, with the remainder consisting of a nickel-based alloy phase and an oxide phase. The area ratio of the chromium carbide phase may be 61.7% or more.

The cylinder rod of a hydraulic cylinder includes a body portion having a bar shape, and a head portion arranged at a longitudinal end of the body portion. The body portion has a coating formed on its outer peripheral surface. The coating includes, in terms of area ratio in cross section, not less than 56.1% and not more than 84.4% of a chromium carbide phase, with the remainder consisting of a nickel-based alloy phase and an oxide phase. The area ratio of the chromium carbide phase may be 61.7% or more.

A thermal spray powder is provided that contains, as constituent elements, a first element selected from W and Mo; a second element selected from Co, Ni, and Fe; a third element selected from C and B; and a fourth element formed of Si. The amount of the second element in the thermal spray powder is 40% by mole or less. The mole ratio of the fourth element to the second element in the thermal spray powder is 0.002 or greater and 0.03 or less. The thermal spray powder has a crystal phase containing Co, Ni, or Fe; W; and C or a crystal phase containing Co, Ni, or Fe; W or Mo; and B. In an X-ray diffraction spectrum of the thermal spray powder, the peak intensity attributed to Co, Ni, or Fe is at most 0.1 times the largest peak intensity in the same X-ray diffraction spectrum.

An apparatus can include a degradable matrix that is degradable in an aqueous environment; and non-degradable particles disposed at least in part within the matrix where the non-degradable particles are not degradable in the aqueous environment where the non-degradable particles can include tungsten carbide.

An apparatus can include a degradable matrix that is degradable in an aqueous environment; and non-degradable particles disposed at least in part within the matrix where the non-degradable particles are not degradable in the aqueous environment where the non-degradable particles can include tungsten carbide.

An apparatus can include a degradable matrix that is degradable in an aqueous environment; and non-degradable particles disposed at least in part within the matrix where the non-degradable particles are not degradable in the aqueous environment where the non-degradable particles can include tungsten carbide.

Provided is a hard sintered body which exhibits excellent high temperature oxidation resistance and has a high hardness at a high temperature. In the hard sintered body, a binder phase is contained at from 8.8 to 34.4 mol % and the balance is composed of a hard phase and inevitable impurities. The binder phase contains iron aluminide containing FeAl as a main component and alumina that is dispersed in iron aluminide and has a particle size of 1 μm or less. The hard phase is composed of at least one kind selected from carbides, nitrides, carbonitrides and borides of Group 4 metals, Group 5 metals and Group 6 metals in the periodic table, and solid solutions of these. This hard sintered body is obtained by mixing and pulverizing a binding particle powder containing an iron aluminide powder composed of at least one kind selected from FeAl.sub.2, Fe.sub.2Al.sub.5 and FeAl.sub.3 and a hard particle powder composed of at least one kind selected from carbides, nitrides, carbonitrides and borides of Group 4 metals, Group 5 metals and Group 6 metals in the periodic table and then sintering a mixed powder thus obtained.

A cemented carbide comprises particles including a tungsten carbide (WC) as a main component; a binder phase including cobalt (Co) as a main component; and particles including a carbide or a carbonitride of at least one selected from the group consisting of Group 4a, 5a, and 6a elements, or a solid solution thereof, wherein a cubic phase free layer (CFL), in which the carbide or the carbonitride is not formed, is formed from a surface of the cemented carbide to a depth of 5 μm to 50 μm.

Mixed powder that contains first hard particles, second hard particles, graphite particles, and iron particles is used to manufacture a sintered alloy. The first hard particle is a Fe—Mo—Cr—Mn based alloy particle, the second hard particle is a Fe—Mo—Si based alloy particle. The mixed powder contains 5 to 50 mass % of the first hard particles, 1 to 8 mass % of the second hard particles, and 0.5 to 1.0 mass % of the graphite particles when total mass of the first hard particles, the second hard particles, the graphite particles, and the iron particles is set as 100 mass %.