Incoloy 800, aluminized treatment

The tubing containing the coupon samples were placed inside a Vycor glass tube (2.2 cm. I. D. and 85 cm.long) that was positioned horizontally in an electrical furnace controlled at either 700 or 900°C. For inorganic gas treatments Incoloy 800 and polished Incoloy 800 coupons were positioned side by side 4. 5 cm. upstream of the reactor midpoint polished and unpolished aluminized Incoloy 800 coupons were likewise positioned side by side except 2.0 cm. upstream... 

Treatments of aluminized (or alonized> Incoloy 800 coupons with helium, oxygen, or steam at 700°C in general resulted in only rather small changes in appearance, as shown in both Figures 3 and 4 for the unpolished and the polished coupons, respective The findings with the polished aluminized coupons must however be considered less reliable. The objective had been to remove only the outer layer that in places was almost pure aluminum and polish until the depth was reached at which aluminum had alloyed with the Incoloy 800. For some coupons, too much or perhaps too little metal was removed, such as for the rough portion of the steam-treated coupon shown in Figure 4C. 

Treatment Aluminized Incoloy 800 Polished Aluminized Incoloy 800... 

An appreciable amount of sulfur (probably as metal su1 f ides> was incorporated in the surface of all coupons exposed to hydrogen sulfide at 700°C as shown in Tables I and II. For Incoloy 800 couponsi there was a very large decrease in the chromium content at the surface. On a sulfur—free basis the iron content increased greatly for polished Incoloy 800 but the nickel content increased for the regular Incoloy 800 coupon. For aluminized Incoloy 800 coupons there was little change in the metal content on a sulfur-free basis as a result of hydrogen sulfide treatments as shown in Table II. 

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