SEDL / STP / STP369-EB / STP43728S

Practical Aspects of Production Bright Annealing of Stainless Steel

Boyer, R. C.
Metallurgist, Republic Steel Corp., Massillon, Ohio.

Perrine, R. J.
Director of research, The Electric Furnace Co., Salem, Ohio.

Pages: 6    Published: Jan 1965

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Abstract

Bright annealing is the annealing of stainless steel sheet and strip continuously in a controlled-atmosphere furnace (depicted). The furnace atmosphere system includes an ammonia storage tank, a dissociator, and an adsorption dryer. Furnace capacity depends upon its specific size, source, temperature, and cooling rate, as well as the emissivity of the material processed. Atmosphere problems are purity and nitrogen pickup. Purity of the dissociated ammonia gas depends upon initial raw ammonia contaminants and dissociator performance. Nitrogen pickup can be prevented by annealing in purified hydrogen atmospheres. Production problems include atmosphere system leakage, maintenance of a temperature head, strip cleaning problems, and crystallized surface. Fabrication problems have included soldering and drawing. The advantages of bright annealed strip are improved surface finish, reduced buffing costs, and improved corrosion resistance.