What Are The Main Product Components Of Near-beta Titanium Alloys?

Near-beta titanium alloys are titanium alloys with a beta stabilizing element content slightly above the critical concentration (the lowest concentration that can retain the high-temperature beta phase to room temperature during rapid cooling). The composition mainly contains beta stabilizing elements such as vanadium, molybdenum, iron and chromium. Has the highest strengthening effect, the highest strength (1200MPa), deeper hardened section (60 ~ 150mm), good tensile plasticity and fracture toughness. Mainly β-III, BT22 and other grades. Vacuum self-consumption arc furnace melting system. Suitable for the manufacture of fasteners and larger cross-section drop-forged parts.
Its composition mainly contains isocrystalline β-stable elements vanadium and molybdenum, eutectic β-stable elements iron and chromium, and a small amount of a-stable elements aluminum, tin and zirconium.

The total content of beta stabilizing elements expressed in molybdenum equivalents ranges between 10% and 13%.

The rapid cooling of these alloys from the β-phase region retains all of the high-temperature β-phase to room temperature, yielding the mechanically unstable sub-stabilized β-phase, i.e., the possibility of a β-a martensitic transformation under external forces.

The aging process precipitates a fine diffuse a-phase from the substable β-phase, which strengthens the alloy. Among the various types of heat-treatable strengthened titanium alloys, near-beta titanium alloys have the highest strengthening effect.

Mechanical properties of β titanium alloys