Spotlight on Alloy 725

09 April 2020

Alloy 725 is a key grade for Special Quality Alloys with a wide range of bar stock and forging capabilities on site here in Sheffield, UK

A precipitation hardenable Nickel-Chromium-Molybdenum based super-alloy with high strength combined with excellent corrosion resistance. Offers similar strength to Alloy 718, with additional benefit of corrosion resistance similar to that provided by Alloy 625.

Stock range

From 25.4mm DIA to 210mm DIA

Processing

From our own ingot/billet stock, we regularly manufacture a wide range of shaped forgings such as rings, blocks and tubing hangers. With on site forging and ring rolling capabilities, we will control the full process through to heat treatment, testing and machining all within the Special Steel Group of companies.

Applicable Specifications

·       API6A CRA

·       ASTM B805

·       NACE MR-0175/ISO 15156

Typical mechanical properties in Solution Annealed and Aged condition.

·       0.2% Yield Strength - 120,000 PSI min                     

·       Tensile Strength  -  150,000 PSI min

·       Elongation  -  20% min

·       Reduction of Area  -  35% min

·       Hardness  -  32HRC min - 43HRC max (NACE)

·       Charpy V-Notch @ -60 DEG C - 43/37 Joules or higher, as per API6A CRA

Chemical Analysis Range

Carbon 0.03% max - Phosphorus 0.015% max - Chromium 19.00% to 22.50% - Silicon - 0.20% max - Sulphur 0.01% max - Manganese 0.35% max - Nickel 55.00% to 59.00% - Molybdenum 7.00% to 9.50% - Titanium 1.00% to 1.70% - Aluminium 0.35% max - Iron (balance) - Niobium (+Tantalum) 2.75% to 4.00%