54 Other important non-ferrous metals

A list of metals and alloys not covered in this topic would be very long. But the three mentioned below are very common “other metals” found in the machine shop.

Titanium

Titanium has developed a mystique as a nightmare to machine. This is simply not the case. Experienced operators have compared its characteristics to those found in 316 stainless steels. Recommended practice includes high coolant flow (to offset the materials low thermal conductivity), slow speeds and relatively high feed rates. Tooling should be tungsten carbide or cobalt-type high speed tools.

Hastelloy ™

Conventional machining techniques used for iron-based alloys may be used. Machining characteristics are somewhat similar to those for the austenitic (300 Series) stainless steels. This alloy does work-harden during machining and has higher strength and “gumminess” not typical of steels.

Inconel ™

Inconel is a nickel-chromium-based superalloy often utilized in extreme environments where components are subjected to high temperature, pressure or mechanical loads. Inconel alloys are oxidation- and corrosion-resistant. When heated, Inconel forms a thick, stable, passivating oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high-temperature applications where aluminum and steel would succumb to creep as a result of thermally induced crystal vacancies. Inconel’s high-temperature strength is developed by solid solution strengthening or precipitation hardening, depending on the alloy.

Conventional machining techniques used for iron-based alloys may be used. This alloy does work-harden during machining and has higher strength and “gumminess” not typical of most steels. Heavy duty machining equipment and tooling should be used to minimize chatter or work-hardening of the alloy ahead of the cutting.

Derived from Inconel – Wikipedia accessed and available 6 December 2024 and The Virtual Machine Shop (2011) http://jjjtrain.com/3engineering/7eng_metalsl_hist/eng_metal_hist_10.html via the WayBack Machine internet archive retrieved 5 March 2024.