Free machining, mon-magnetic, stainless steel alloy

• US 5,087,414 A
• Filed: 03/28/1990
• Issued: 02/11/1992
• Est. Priority Date: 11/03/1989
• Status: Expired due to Term

• Current Assignee: CRS Incorporated (Carpenter Technology Corporation)
• Original Assignee: Carpenter Technology Corporation
• Inventors: Maniar, Gunvant N.
• Primary Examiner(s): Yee, Deborah
• Application Number:
  US07/500,521
• Time in Patent Office: 685 Days
• Field of Search: 420/43, 420/52, 420/42, 148/327
• US Class Current: 420/43
• CPC Class Codes: C22C 38/40 with nickel
• CPC Class Codes: H01H 35/14 Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch wherein the liquid constitutes a contact of the switch H01H29/002

Abstract

This invention provides a non-magnetic, austenitic, corrosion resistant stainless steel alloy having improved machinability, a consistently reproduceable coefficient of thermal expansion, and an essentially ferrite-free structure. The alloy contains about 0.04-0.10 w/o C, 0.03-0.07 w/o N, 2.00 w/o max. Mn, 1.00 w/o max, Si, 0.045 w/o max. P, 0.015-0.10 S, 19.00-24.00 Cr, 0.75 w/o max. Mo, 12.00-18.00 w/o Ni, and the balance iron. The alloy is balanced so that no more than about 2 v/o ferrite as determined by the DeLong diagram is present and so that the coefficient of thermal expansion is about 14.5×10^-6 to 16.5×10^-6 per C.° within the temperature range of about -51 to 121 C.

This invention further provides articles, including a non-magnetic tube in a magnetically biased accelerometer having good corrosion resistance, a coefficient of thermal expansion of about 14.5×10^-6 to 16.5×10^-6 per C.° within the temperature range of about -51 to 121 C., and containing no more than about 2 v/o ferrite as determined by the DeLong diagram and therefore, being non-magnetic.

Claims

1. A non-magnetic, austenitic, corrosion resistant alloy consisting essentially of, in weight percent, about

View Dependent Claims (2, 3, 4, 5, 8, 10, 11, 12, 13, 14, 15, 16)

2. The alloy as recited in claim 1 wherein said alloy contains 0 v/o ferrite as determined by the DeLong diagram.

3. The alloy as recited in claim 1 having a coefficient of thermal expansion in the range of about 15.25×

10^-6 -16.25×

10^-6 per C.°

.

4. The alloy as recited in claim 1 containing at least 0.05 w/o carbon and no more than 0.06 w/o nitrogen.

5. The alloy as recited in claim 4 containing no more than about 0.07 w/o carbon.

8. A fabricated article formed from the alloy of claim 1.

10. An alloy as recited in claim 5 containing about 0.030% max. phosphorus.

11. An alloy as recited in claim 10 containing not more than about 0.030% sulfur.

12. An alloy as recited in claim 11 containing about 0.50% max. molybdenum.

13. An alloy as recited in claim 12 containing at least about 14.50% nickel.

14. An alloy as recited in claim 13 containing at least about 1.50% manganese.

15. An alloy as recited in claim 14 containing about 0.40% max. silicon.

16. An alloy as recited in claim 15 containing at least about 22.00% chromium.

6. A non-magnetic, austenitic, corrosion resistant alloy consisting essentially, of, in weight percent, about

View Dependent Claims (9)

9. A fabricated article formed from the alloy of claim 6.

7. A non-magnetic, austenitic, corrosion resistant alloy consisting essentially of, in weight percent, about