1.4886, often known by its Rolled Alloys brand name RA330®, is a high temperature austenitic stainless steel with superior performance to standard grades such as 310.
Approximate Composition – 18% Cr, 35.0% Ni, Si 1.25%, 0.05% C (Exact composition ranges vary between EN and ASTM standards).
This grade combines the following characteristics:
- Excellent oxidation resistance up to 1150°C
- Excellent carburisation resistance up to 1150°C
- Excellent thermal shock resistance
- Good resistance to oxidising sulphur atmospheres
- Excellent resistance to sigma phase formation
- Excellent stress corrosion cracking resistance
- Good weldability
This grade is regarded as one the best all-round high temperature stainless steels due to its chromium and high nickel content. Indeed, it is classed as a nickel alloy in the UNS system. The addition of silicon gives it carburisation resistance. Its fully austenitic structure and the absence of elements such as molybdenum give it a high resistance to forming embrittling sigma phase.
Applications which illustrate these features include:
Muffles, retorts, heat treatment baskets, refractory fixings, salt pots, radiant tubes, conveyors, furnace fans.