Iron based alloy suitable for providing a hard and wear resistant coating on a substrate, article having a hard and wear resistant coating, and method for its manufacture
The present invention relates to an iron-based alloy that is able to provide a coating on a substrate, the coating having simultaneously high hardness and wear resistance. The iron-based alloy consists of 3.0-7.0% by weight Cr; 1.3-3.0% by weight C; 0.2-2.0% by weight B; 2.0-10.0% by weight V; optionally 1.5% by weight or less Si; optionally 1.0% by weight or less Mn, optionally 2.0% by weight or less Mo; optionally 1.5% by weight or less Ni; the balance being Fe and unavoidable impurities. The present invention further relates to an article comprising a substrate and coating formed thereon, the coating being formed from the alloy, and to a method for forming a coated article. The method preferably employs HVOF, laser cladding or plasma cladding.
1. An iron-based alloy, consisting of
3.0-7.0% by weight Cr;
1.3-3.0% by weight C;
0.3-2.0% by weight B;
2.0-10.0% by weight V;
1.5% by weight or less Ni, wherein the content of Ni is greater than 0;
optionally 1.5% by weight or less Si;
optionally 1.0% by weight or less Mn,
optionally 2.0% by weight or less Mo;
the balance being Fe and unavoidable impurities.
2. The iron-based alloy according to claim 1 , wherein the content of Cr is from 3.2-6.8% by weight.
3. The iron-based alloy according to claim 1 , wherein the content of B is from 0.3-1.2% by weight.
4. The iron-based alloy according to claim 1 , wherein the content of Ni is greater than 0 and is 1.0% by weight or less.
5. The iron-based alloy according to claim 1 , wherein the content of Mo is greater than 0.
6. The iron-based alloy according to claim 1 , wherein the content of V is from 4.0 to 8.0% by weight.
7. The iron-based alloy according to claim 1 , wherein the content of C is from 1.5-2.8% by weight.
8. The iron-based alloy according to claim 1 , wherein the content of the optional components Si, Mn, and Mo is each 1.0% by weight or less.
9. An article having a substrate and a coating, the coating being formed from an iron-based alloy as defined in claim 1 .
10. The article according to claim 9 , wherein the substrate is made of a metal or metal alloy.
11. Article according to claim 9 , which is a hydraulic cylinder or roller used in the mining or steel industry.
12. The article according to claim 11 , wherein the coating has both
a hardness of 60 HRC or greater as measured by SS-EN ISO 6508-1:2016; and
a wear of 25 mm 3 or less according to ASTM G65-16, Procedure A.
13. The article according to claim 9 , wherein the coating is formed by laser cladding, plasma powder cladding or plasma transfer arc, wherein the content of the optional components Si, Mn, and Mo is each 1.0% by weight or less in the iron-based alloy powder.
14. The iron-based alloy according to claim 1 , which is in powder form.
15. A method of forming a coating on a substrate with the iron-based alloy according to claim 1 .
16. An iron-based alloy, consisting of
3.0-7.0% by weight Cr;
1.3-3.0% by weight C;
0.3-2.0% by weight B;
2.0-10.0% by weight V;
optionally 1.5% by weight or less Si;
optionally 1.0% by weight or less Mn,
optionally 2.0% by weight or less Mo;
optionally 1.5% by weight or less Ni;
the balance being Fe and unavoidable impurities,
wherein the iron-based alloy is in powder form.
17. The iron-based alloy according to claim 16 , wherein the powder contains no or less than 2% by weight of particles having a particle size exceeding 250 μm as measured by sieve analysis according to ASTM B214-16.
18. The iron-based alloy in powder form according to claim 16 , which consists of particles having a particle size between 5-200 μm as measured by sieve analysis according to ASTM B214-16.
19. The iron-based alloy in powder form according to claim 16 , which consists of particles having a particle size between 20-200 μm as measured by sieve analysis according to ASTM B214-16.
20. A method for forming a coated article, comprising the steps of
providing a substrate, and
forming a coating on the substrate,
wherein the step of forming the coating utilizes an alloy powder as defined in claim 16 .
21. The method for forming a coated article according to claim 20 , wherein the step of forming a coating is a laser cladding step, a plasma powder cladding step, a plasma transfer arc step or a HVOF step.
22. The method for forming a coated article according to claim 20 , wherein the article is a hydraulic cylinder or roller used in the mining or steel industry.