Browse Prior Art Database

Vacuum Heat Treating

IP.com Disclosure Number: IPCOM000075132D
Original Publication Date: 1971-Aug-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 2 page(s) / 49K

Publishing Venue

IBM

Related People

Loomis, RP: AUTHOR [+3]

Abstract

Easily oxidized tool steel parts are heat-treated in a vacuum using a furnace open to the atmosphere.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 71% of the total text.

Page 1 of 2

Vacuum Heat Treating

Easily oxidized tool steel parts are heat-treated in a vacuum using a furnace open to the atmosphere.

The part is encased in a closely fitting metal enclosure having one external opening through which passes a closure rod. The enclosure is constructed by welding a flat cut sheet (Figs. 1 and 2) or by slicing sections from a tube (Fig. 3). One end of the closure rod is welded to an inside surface of the enclosure, and the other end has an enlargement, about the size of the opening, which provides material for welding shut the opening. The enclosure, completely sealed except for the one opening, is placed in a high-vacuum electron-beam welder which evacuates the enclosure and then welds shut the opening. After heat treating, the part is removed by grinding off three or four edges, or sawing off one end, of the enclosure.

If the enclosure is only slightly larger than the part, no part holders are necessary. A clamp, (Fig. 3) is desirable if one part is to be vacuum brazed to another part during heat treating or if the part is made from a material, such as laminated sheets, which must be kept from buckling. If desired, the part may be held in place by studs (Fig. 2) or clamps, etc. Heat treating may include a salt bath, oil quenching, air tempering, etc. A closely fitted enclosure providing intimate contact with most sides of the part is necessary for oil quenching.

For a 2-1/2 inch thick part made of manganese air hardening steel (AISI Type A6)...