High strength and corrosion resistant ferrochrome alloy bulk and article comprising the same

Patent metadata

Field	Value
Publication number	US-12168820-B2
Application number	US-202117385990-A
Country	US
Kind code	B2
Filing date	Jul 27, 2021
Priority date	Jun 30, 2021
Publication date	Dec 17, 2024
Grant date	Dec 17, 2024

Abstract

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.

First claim

What is claimed is:

1. A high strength and corrosion resistant ferrochrome alloy bulk, being made by sequentially applying a melting process of raw materials in a crucible and a solidification process to cast as an ingot, so as to have a hardness greater than HV400 but lower than HV900; wherein the high strength and corrosion resistant ferrochrome alloy bulk consists of, in weight percent:
39-68% Cr;
2.5-5.5% Ni;
2.5-6% C;
at most 4.5% M; and
the balance Fe;
wherein M consists of at least one additive element that is selected from a group consisting of B, Al, Si, Sn, Ti, V, Mn, Co, Cu, Zr, Nb, and Mo, and a summation of B, AL, Si, Sn, Ti, V, Mn, Co, Cu, Zr, Nb, and Mo content is less than or equal to 4,5%;
wherein a Fe/Ni ratio is in a range from 6 to 10, and a Cr/C ratio being in a range between 10 and 20; and
wherein in case of M including Si, a content of Si being smaller or equal to 1.5%.

2. The high strength and corrosion resistant ferrochrome alloy bulk of claim 1 , being processed to be in an as-cast state, or being in a heat-treated state after being applied with a heat treatment that is selected from a group consisting of precipitation hardening treatment, annealing treatment and homogenization treatment.

3. An article, being made of a high strength and corrosion resistant ferrochrome alloy bulk, wherein the high strength and corrosion resistant ferrochrome alloy bulk is made by sequentially applying a melting process of raw materials in a crucible and a solidification process to cast as an ingot, so as to have a hardness greater than HV400 but lower than HV900; wherein the high strength and corrosion resistant ferrochrome alloy bulk consists of, in weight percent:
39-68% Cr;
2.5-5.5% Ni;
2.5-6% C;
at most 4.5% M; and
the balance Fe;
wherein M consists of at least one additive element that is selected from a group consisting of B, Al, Si, Sn, Ti, V, Mn, Co, Cu, Zr, Nb, and Mo, and a summation of B, Al, Si, Sn, Ti, V, Mn, Co, Cu, Zr, Nb, and Mo content is less than or equal to 4.5%;
wherein a Fe/Ni ratio is in a range from 6 to 10, and a Cr/C ratio being in a range between 10 and 20; and
wherein in case of M including Si, a content of Si being smaller or equal to 1.5%.

Assignees

• Univ Nat Tsing Hua

Inventors

• Yeh Jien-Wei

Classifications

• C22C1/03

  using master alloys · CPC title

• B22F5/008

  of engine cylinder parts or of piston parts other than piston rings (of piston rings B22F5/02) · CPC title

• B22F5/04

  of turbine blades · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title

• Y02P10/25

  Process efficiency · CPC title