Page 8 of 8 FirstFirst ... 678
Results 71 to 72 of 72

Thread: QuliMetal Grates

  1. #71
    New Member
    Join Date
    Apr 2019
    Southampton, UK
    Quote Originally Posted by Jon Tofte View Post
    My hunch is that high grade 304 stainless (like on my Broilmaster) is not at all magnetic but commonly used 430 stainless is very magnetic. So, these grates that show just a slight level of magnetism can't be written off as 430 but perhaps are not pure, high-grade 304 stainless.
    Jon, you might be interested in this article in Scientific American.

    "At room temperature, the thermodynamically stable crystal structure of 304 stainless steel is body centred cubic (bcc); nevertheless, the alloy's nickel concentration, as well as the small amounts of manganese (about 1 percent), carbon (less than 0.08 percent) and nitrogen (about 0.06 percent), maintains a face centred cubic (fcc) structure and therefore the alloy is nonmagnetic. If the alloy is mechanically deformed, i.e. bent, at room temperature, it will partially transform to the ferritic phase and will be partly magnetic, or ferromagnetic, as it is more precisely termed."

    So it seems to be mechanical deformation of 304 at room temperature that introduces the partial magnetism rather than any impurity or welding. It would return to a completely non-magnetic form by annealing at a suitably high temperature, but I doubt it will get hot enough in use on the grill for that.

  2. #72
    TVWBB Fan
    Join Date
    May 2019
    Brookfield, NS
    Robert, that would explain why the burner tubes I got were slightly magnetic only at the ends where they are pinched, hence deformed. I wondered about that! Thanks for the informative post.

Page 8 of 8 FirstFirst ... 678

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts