UGI® HT286 Annealed: High-Performance Austenitic Alloy for Cryogenic to 700°C Applications

UGI® HT286 has an oxidation resistance comparable to that of type AISI 310 stainless steel, up to 800°C. The corrosion resistance of this alloy is excellent up to 700°C in many atmospheres encountered in jet engine services. Its good resistance to high-temperature oxidation and intergranular corrosion, together with its absence of cobalt, non-magnetic structure and a higher yield strength than conventional stainless steel, have led to widespread use of UGI® HT286 for fasteners in the aerospace, nuclear, automotive and chemical engineering industries.

UGI® HT286 is more difficult to machine than standard stainless steels, mainly because of the very low sulphur content required to guarantee that this grade has a good hot workability. Without sulphide content, during machining UGI® HT286 produces long chips that are difficult to manage, especially in drilling operations.

Because of its high mechanical characteristics in the aged condition (even at the temperatures reached in the vicinity of the cutting tool), UGI® HT286 is often machined in its annealed condition. But, in this condition, sticking and edge build-up phenomena on the tools used results in poor tool life and a very bad surface finish. It can therefore be advisable to increase the mechanical characteristics of the material in its annealed condition through cold working or through an ‘ageing’ heat treatment prior to machining. Compared to other superalloys, relatively high speeds can be used to machine UGI® HT286. During machining, this grade is subject to work hardening, inducing tough chips but also a harder machined surface than the original material. This results in notching and chipping during subsequent machining passes. Sharper, more positive cutting edges reduce this phenomenon and are therefore preferred. Generally CVD (chemical vapor deposition) coatings are preferred for improved speed capability and longer tool life.

Solution annealing: 1 hour at 980°C, followed by water cooling

Available products:

(1)With or without soap coating

Other products: contact the supplier