Titanium
Titanium alloys were already well known in aerospace and petrochemical sector, for offshore stations, and in other applications, such as building, for example the famous Guggenheim museum in Bilbao.
Titanium alloys were also used in F1 for machined or fabricated parts, but had never been used for castings with RP patterns.
CRP introduced for the first time in the world the Titanium Rapid Casting.
Moreover, of course, these alloys are also CNC machined from billets.
Some positive aspects of titanium alloys (Ti6Al4V):
- lightness
(density 4,43 g/cm3)
- high specific Ultimate Tensile Strength
(225,73 gMPa/cm3 per density unit)
(UT S 1000 Mpa)
- bio-compatibility
- low thermal and electrical conductivity
- corrosion and stress corrosion resistance (SCC)
Advantages given by heat treatments of casting:
- stress reduction
- ductility
- workability
- dimensional and structural stability
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Ti-6AI-4V is the most used alloy, particularly the one used by CRP. It contains 6% of aluminium and 4% of vanadium, an
excellent combination of stress resistance and toughness, with optimal wear resistence. The Solution Treatment and Ageing process (the
STA) was developed to increase UTS (Ultimate Tensile Strength).
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F1 upright. Titanium casting & CNC machining
Upright for F1 made by investment casting with Titanium alloy (Ti-6Al4V) and disposable SLS Rapid Prototyping pattern. Box-type geometry with TIG welded cast patches.
Post-casting treatments: H.I.P. (Hot Isostatic Pressing), Chemical Mill, Annealing HT.
CNC machining and 3D inspection only where required.
Characteristics: Complex design to increase part performance. High mechanical properties and reliability.
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The heat treatment that CRP usually applies is the
Process Annealing.
Annealing is a quite generic term and indicates the process used to improve toughness, ductility at room temperature, dimensional and structural stability and, sometimes, Creep resistance.
Some treatments are usually applied to Titanium alloys castings, due to Titanium high reactivity, besides typical methods to obtain a good casting:
- Chemical mill: to remove alpha case structure that originates from the contact between metal and ceramic shell
- Hip: Hot Isostatic Pressure applied in an inert atmosphere (argon) to eliminate micro- porosity and lacks of material inside the casting
- Weld repair: TIG weld repair in inert atmosphere, to fill in porosity or HIP hollows, searched with real time RX inspections
- Shot peening: under-control shot-peening to reduce stress and increase fatigue resistance.
Two small hydraulic parts for F1 gearbox
Ti-6Al4V CNC machining.
A jewel of mechanics for F1, fully machined from a round bar of Ti-6Al4V AMS 4928.
Characteristics: High surface quality and high thickness control.
High mechanical properties and reliability. Nice and fine details.
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download datasheet for Ti_6Al4Vfuso (
