Menu
CSS SHEET - CONTACT DETAILS

New High Strength Corrosion Resistant MP35N™

Broder Metals Group Ltd are pleased to announce another addition to our Oil & Gas bar stock range with the introduction of grade MP35N.

This is a nickel-cobalt alloy only manufactured by Latrobe in the US and provides a unique combination of properties including ultra high strength, toughness, ductility, and outstanding corrosion resistance.

The high strength variant of MP35N™ is used in the medical and aerospace industry while material produced for the oil and gas applications has less cold work reduction than the full strength variant to give the material better stress corrosion cracking (SCC) resistance for harsh environments, and in order to conform to NACE MR0175 / ISO 15166-3 (2009). In this condition the material resists corrosion in hydrogen sulphide, salt water and other chloride environments, as well as resists attack from mineral acids (nitric, hydrochloric and sulphur). The material has exceptional resistance to crevice and stress corrosion cracking in sea water and other hostile environments.

The amount of cold work applied defines at what temperature the material is aged to achieve the final properties required. Typically for optimum sulphide stress corrosion cracking (SCC) resistance the material is aged at 1300 / 1350 deg F for 4 hours (more strength / slightly less SCC resistance) or at 1425 deg F for 6 hours (better SCC resistance / less strength)

The material is suitable for use in the manufacture of fasteners, springs, non-magnetic electrical components, instrument parts, valve components, high pressure door fittings, actuators, seals, shafts and other components.

Initial stock sizes:

  • 1” – 25.4 mm dia
  • 1.335” – 33.91 mm dia
  • 2” – 50.8 mm dia
  • 2.75” – 69.85 mm dia
  • 3” – 76.2 mm dia

Material can also be supplied as cold drawn tubing (from Latrobe stock) in the following sizes:

  • 1.312” (33.3 mm) OD x 1” (25.4 mm) ID
  • 2.610” (66.3 mm) OD x 2.190” (55.6 mm) ID

Material will be supplied against the following Standards as applicable:

  • AMS 5845 – solution heat treated, cold drawn and aged bars
  • NACE MR 01-75 – sulphide stress cracking resistant material for oil field equipment
  • AMS 7468 – bolts and screws, forged head, roll threaded after ageing

Mechanical Tests are conducted at room temperature in accordance with ASTM E8,; hardness in accordance with ASTM E18; Macrotech in accordance with ASTM A604, Grain Size in accordance with ASTM E112.

Applicable customer specs:

  • CAMERON: MS-003064-()
  • AKER: 10001000124-PDC-000
  • EXPRO: MS-1157
  • ENOVATE: EN-SPEC-00307

Mill lengths supplied: 7-16 ft (2.1 – 4.88 m), although we will cut to lengths required if necessary.

Diameter tolerance: +/- 0.003” (0.076 mm)

Density: 8.43 g/cm3

Chemistry:

Element Composition
Ni 33 – 37 %
Co Balance (usually about 35%)
Cr 19 – 21 %
Mo 9 – 10.5%
C 0.025% max
Mn 0.15% max
Si 0.15% max
P 0.015% max
S 0.01% max
Fe 1% max
Ti 1% max
B 0.15% max

Melting: MP35N™ is produced by vacuum induction melting followed by VAC-ARC remelting to provide exceptional control of chemistry and ingot solidification.

ASTM Grain size is 4 or finer.

MP35N™ has a face centred cubic structure matrix of cobalt and nickel, in which chromium and molybdenum are soluble at elevated temperatures. The fcc structure persists upon cooling to room temperature and below.

Note: Exposure to temperatures above the recommended ageing levels may result in a significant (and non-reversible) loss of strength caused by the reversion of the cold worked metallurgical structure to a much softer annealed structure.

Heat Treatment

Treatment Temperature Time Cooling Note
Solution Treat 1900 -1925 deg F 4 – 8 hours Air
Age One of (to meet NACE MR0175) [after cold working]
1300 deg F 4 hours min Air
1350 deg F 4 hours min Air
1425 deg F 6 hours min Air
1450 deg F 4 hours min Air

Increasing ageing temperature & time provides better SCC resistance but lower strength.

Mechanicals

Typical mechanical properties of cold drawn (reduced strength) material for the oil and gas industry

Spec Guaranteed minimums up to 2” dia
UTS
ksi
YS (0.2%)
ksi
Elong % (4D) RA % HRC
Age 1300 deg F / Time 4 hours 210 200 10 40 51 max
Age 1350 deg F / Time 4 hours 220 210 10 40 51 max
Age 1425 deg F / Time 6 hours 190 180 10 40 51 max

Current stock mechanicals

Size Ageing UTS
ksi
Offset
ksi
Elong
%
R of A
%
HRC Grain size
25.4 mm 1425/6 213.9 203.21 19 51 41-46 7
33.9 mm 1425/6 212.7 203.8 19 62 42 4.5
50.8 mm 1425/6 203-206 184-195 20-21 58-62 39-45 5.5
69.85 mm 1300/4 196 182 25 59 40.5 4
76.2 mm 1300/4 199 188 21 62 37-38 5.6 – 6.0

UT – acc to ASTM A388 – 100% volumetric

Expected Impact values

Test Direction Test Temp Min Ft Lbs Min Joules Av Ft lbs Av Joules
Longitudinal -22 (F) / -30 C 20 27 15 20
Transverse -22 (F) / -30 C 15 20 12 15

(Note: MP35N is a trademarked grade (produced by [Timken] Latrobe Speciality Steel, a subsidiary of Carpenter Technology in the USA, and the trademark is owned by SPS Technologies Inc).

Comments are closed.