Stainless steel users will see a substantial hike in what they pay for flat-rolled material in February, renewing concerns about substitution.

The nation's three major stainless mills—AK Steel Corp., Middletown, Ohio; Allegheny Technologies Inc. (ATI), Pittsburgh; and North American Stainless Inc. (NAS), Ghent, Ky.—all announced surcharge increases for the coming month due to rising nickel prices.

AK Steel came in at the high end of the range, posting surcharges of $1.4215 a pound for Type 304 material, up 9 percent from $1.3047 in January; $2.2642 a pound for Type 316, up 5.8 percent from $2.1394; and $1.6025 a pound for Type 321, up 8.8 percent from $1.4731.

ATI and NAS are pretty much on par for February, differing only slightly in their surcharges for Type 321 material—$1.5916 a pound by ATI (up 7.4 percent from $1.4825) and $1.5917 by NAS (up 8.4 percent from $1.4678). The two companies posted February surcharges of $1.4106 a pound for Type 304 material (up 7.3...