Raw material powder for laser clad valve seat and valve seat using the same
View Patent ↗There are disclosed a laser clad valve seat raw-material powder superior in productivity, cladding property, wear resistance and finishing property, and a laser clad valve seat using the same superior in wear resistance. The row-material powder comprises a powder mixture comprising: 80 to 99% by weight of a Cu-based alloy powder comprising 0.5 to 5% by weight of B, 0 to 20% by weight of Ni, 0 to 10% by weight of Fe plus Co, 0 to 5% by weight of Si, 0 to 3% by weight of Al, and the balance Cu and unavoidable impurities; and 1-20% by weight of an Fe or Co based alloy powder having a Vickers hardness of 500 HV or higher and an average particle diameter of 50 to 200 μm of and comprising 5 to 40% by weight of Mo, 0 to 25% by weight of Cr, 0 to 5% by weight of Si, and the balance Fe or Co and unavoidable impurities.
1. A raw-material powder for a laser clad valve seat, comprising a powder mixture of:
a Cu based alloy powder of 80% to 99% by weight of the powder mixture comprising:
B: 0.5 to 5% by weight,
Ni: 0 to 20% by weight,
Fe plus Co: 0 to 10% by weight,
Si: 0 to 5% by weight,
Al: 0 to 3% by weight, and
the balance Cu and unavoidable impurities; and
an Fe or Co based alloy powder of 1 to 20% by weight of the powder mixture, having a Vickers hardness of 500 HV or higher and an average particle diameter of 50 to 200 μm and comprising:
Mo: 5 to 40% by weight,
Cr: 0 to 25% by weight,
Si: 0 to 5% by weight, and
the balance Fe or Co and unavoidable impurities.
2. The raw-material powder according to claim 1 , wherein the Cu based alloy powder comprises:
B: 0.5 to 5% by weight,
Ni: 7 to 20% by weight,
Fe plus Co: up to 10% by weight,
Si: 2 to 5% by weight,
Al: up to 3% by weight, and
the balance Cu and unavoidable impurities, and the Fe or Co based alloy powder comprises:
Mo: 5 to 40% by weight,
Cr: up to 25% by weight,
Si: up to 5% by weight, and
the balance Co and unavoidable impurities.
3. A laser clad valve seat comprising a laser clad layer formed by laser-cladding with the powder mixture according to claim 1 .
4. The laser clad valve seat according to claim 3 , wherein the laser clad layer contains coarse particles, and the coarse particle has a shell structure in which Mo based boride surrounds a phase mainly comprising an Fe or Co based alloy comprising 5 to 40% by weight of Mo, 0 to 25% by weight of Cr, 0 to 5% by weight of Si, and the balance Fe or Co and unavoidable impurities.
5. The laser clad valve seat according to claim 4 , wherein the phase mainly comprising the Fe or Co based alloy comprise 5 to 40% by weight of Mo, up to 25% by weight of Cr, up to 5% by weight of Si, and the balance Co and unavoidable impurities.
6. The laser clad valve seat according to claim 4 , wherein the coarse particle has a Vickers hardness of 500 HV or higher and an average particle diameter of 30 to 300 μm.
7. A laser clad valve seat comprising a laser clad layer formed by laser-cladding with the powder mixture according to claim 2 .
8. The laser clad valve seat according to claim 7 , wherein the laser clad layer contains coarse particles, and the coarse particle has a shell structure in which Mo based boride surrounds a phase mainly comprising an Fe or Co based alloy comprising 5 to 40% by weight of Mo, 0 to 25% by weight of Cr, 0 to 5% weight of Si, and the balance Fe or Co and unavoidable impurities.
9. The laser clad valve seat according to claim 8 , wherein the phase mainly comprising the Fe or Co based alloy comprise 5 to 40% by weight of Mo, up to 25% by weight of Cr, up to 5% by weight of Si, and the balance Co and unavoidable impurities.
10. The laser clad valve seat according to claim 9 , wherein the coarse particle has a Vickers hardness of 500 HV or higher and an average particle diameter of 30 to 300 μm.
11. The laser clad valve seat according to claim 5 , wherein the coarse particle has a Vickers hardness of 500 HV or higher and an average particle diameter of 30 to 300 μm.