Engine building mailing list?

[Jay Wallace]

At 10:26 AM 11/19/98 -0800, you wrote:
>Hi Barrett
>
>What's hipping?
>

HIP = Hot Isostatic Press. Put the material in a sealed furnace and
apply a gas pressure at elevated temperatures to it in order to
remove any closed flaws (pores, etc) in the part. Used for things
like turbine blades where creep deformation has resulted in
internal cavity formation. The small lab HIP that I use for sinter
/ HIP'ing silicon nitride can go to about 2100 C (3800 F) and 200
MPa (20,000 psi) in nitrogen or argon.

Jay