Alloy compositions
The present disclosure provides compositions comprising iron, about 0.01 to about 0.4% w/w of manganese; about 1.3 to about 1.9% w/w of chromium; about 0.1% w/w or less of nickel; about 1.2 to about 1.7% w/w of molybdenum; about 0.01 to about 0.4% w/w of niobium; about 0.01 to about 0.4% w/w of vanadium; about 1.5 to about 2% w/w of silicon; and about 0.01 to about 0.20% w/w of carbon. The present disclosure also provides methods of preparing a metal powder, comprising atomizing a composition described herein and methods of preparing a metal object, comprising subjecting metal powder described herein to metal binder jetting.
1 . A method of preparing a dual-phase microstructure sintered metal object, comprising:
(i) atomizing an iron-based composition to form a metal powder, wherein the iron-based composition comprises:
0.01 to 0.4% w/w of manganese;
1.3 to 1.9% w/w of chromium;
0.1% w/w or less of nickel;
1, 2 to 1.7% w/w of molybdenum;
0.01 to 0.4% w/w of niobium;
0.01 to 0.4% w/w of vanadium;
1.5 to 2% w/w of silicon; and
0.01 to 0.16% w/w of carbon;
wherein the balance of the iron-based composition comprises iron and the iron comprises no more than 1.0% w/w, based on the total weight of the iron-based composition, of normal impurities;
(ii) depositing two or more layers of the metal powder to form a component; and
(iii) sintering the component at a temperature for the sintering is 700 to 1500° C. to provide a two phase microstructure comprising austenite and ferrite and having a density of at least 7 g/cm 3 ; and
(iv) cooling the component of (iii) to provide the dual-phase microstructure sintered metal object comprising (a) ferrite and (b) at least one of martensite or bainite.
2 . The method of claim 1 , wherein the iron-based composition comprises 0% w/w of nickel.
3 . The method of claim 1 , wherein the iron-based composition comprises 0.04 to 0.1% w/w of nickel.
4 . The method of claim 1 , wherein the iron-based composition comprises 0.1 to 0.3% w/w of manganese.
5 . The method of claim 1 , wherein the iron-based composition comprises 1.4 to 1.8% w/w of chromium.
6 . The method of claim 1 , wherein the iron-based composition comprises 1.3 to 1.6% w/w of molybdenum.
7 . The method of claim 1 , wherein the iron-based composition comprises 0.1 to 0.3% w/w of niobium.
8 . The method of claim 1 , wherein the iron-based composition comprises 0.1 to 0.3% w/w of vanadium.
9 . The method of claim 1 , wherein the iron-based composition comprises 1.5 to 1.8% w/w of silicon.
10 . The method of claim 1 , wherein the iron-based composition comprises 0.05 to 0.14% w/w of carbon.
11 . The method of claim 1 , wherein the iron-based composition further comprises sulfur.
12 . The method of claim 11 , wherein the iron-based composition comprises 0.001 to 0.015% w/w of sulfur.
13 . The method of claim 1 , wherein the iron-based composition further comprises oxygen.
14 . The method of claim 13 , wherein the iron-based composition comprises 0.01 to 0.1% w/w of oxygen.
15 . The method of claim 1 , wherein the iron-based composition further comprises nitrogen.
16 . The method of claim 15 , wherein the iron-based composition comprises 0.01 to 0.02% w/w of nitrogen.
17 . The method of claim 1 , wherein the metal powder has a d 10 particle size of 1 to 10μ, a d 50 particle size of 10 to 20μ, or a do particle size of 20 to 30μ, or combinations thereof.
18 . The method of claim 1 , wherein the atomizing is gas or water atomizing.
19 . The method of claim 1 , wherein the layers are bound together using a liquid binding agent.
20 . The method of claim 1 , wherein the depositing is performed on a metal substrate.
21 . The method of claim 1 , further comprising annealing the sintered metal object.
22 . The method of claim 21 , wherein an intercritical temperature for the annealing is 600 to 1000° C.
23 . The method of claim 1 , wherein the iron-based composition further comprises:
0.001 to 0.015% w/w of sulfur;
0.01 to 0.1% w/w of oxygen; and
0.01 to 0.02% w/w of nitrogen.
24 . The method of claim 1 , wherein the iron-based composition comprises:
0.1 to 0.3% w/w of manganese;
1.4 to 1.8% w/w of chromium;
0.04 to 0.1% w/w of nickel;
1.3 to 1.6% w/w of molybdenum;
0.1 to 0.3 w/w of niobium;
0.1 to 0.3 w/w of vanadium;
1.5 to 1.8% w/w of silicon; and
0.05 to 0.14% w/w of carbon.
25 . The method of claim 1 , wherein the iron-based composition comprises:
0.01 to 0.4% w/w of manganese;
1.3 to 1.9% w/w of chromium;
0.1% w/w or less of nickel;
1, 2 to 1.7% w/w of molybdenum;
0.01 to 0.4% w/w of niobium;
0.01 to 0.4% w/w of vanadium;
1.5 to 2% w/w of silicon; and
0.01 to 0.16% w/w of carbon.
26 . The method of claim 1 , wherein the iron-based composition consists essentially of:
0.01 to 0.4% w/w of manganese;
1.3 to 1.9% w/w of chromium;
0.1% w/w or less of nickel;
1, 2 to 1.7% w/w of molybdenum;
0.01 to 0.4% w/w of niobium;
0.01 to 0.4% w/w of vanadium;
1.5 to 2% w/w of silicon; and
0.01 to 0.16% w/w of carbon.