Searching for a Furnace Fixture Alloy?

There are many different types of furnace fixtures and many different alloys to choose from, but for many furnace and other high temperature applications, RA330® is a logical first choice. Since being introduced in the early 1950’s as the wrought counterpart to cast alloy HT, RA330 has proven its worth in oxidizing, carburizing and carbonitriding heat treating applications. Of course it performs well in inert or reducing environments as well, but the high chromium content offers excellent oxidation resistance at temperatures up to 2100° F.

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The true advantages of RA330 are very apparent in carburizing or carbonitriding furnaces where the atmosphere is neutral to the steel parts being heat treated, but is damaging to baskets or other structural fixtures exposed in the furnace. The high nickel content of RA330 resists absorption of carbon. Nickel also helps the alloy maintain reasonable ductility even after carburization has begun. Many operators report being able to mechanically straighten fixtures after distortion resulting from extended service or physical damage.

Rolled Alloys unique manufacturing requirements also result in a material that resists thermal fatigue. Water quenching of fixtures is very hard on the materials performance and RA330 is recognized for outperforming other high nickel alloys in this regard.

The alloy also offers good elevated temperature strength. Stronger alloys are available, but few can come close to matching the combination of oxidation/carburization resistance, strength and economics of RA330. The alloy is also readily formed and welded.

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Rolled Alloys offers a range of alloys that are useful in high temperature environments. We offer baseline heat resistant alloys such as 304H that are suitable for temperatures in air up to 1400° F. We also carry more specialized stainless alloys such as 310 and RA 253MA©, and nickel alloys such as RA 602CA© that can perform at temperatures of 2250° F with remarkable strength. RA330 is a workhorse in the industrial heating arena and is a great place to start when beginning the selection process.