TungstenIts strength is “white hot”, therefore allowing applications up to 2900 °C (3173 K). This also explains the probably most frequent use as the glow wire in incandescent bulbs.
In terms of its physical and chemical values, tungsten embodies the typical properties of refractive metals. These include all metals whose melting point is above that of platinum (1772 °C). Tungsten is primarily used as a base material in many tungsten alloys, such as tungsten-lanthanum oxide (WL), tungsten heavy alloys (WHA) and tungsten-copper (EROMET). In its pure form, it is used in far fewer applications, such as crucibles for the coating industry, and as a heat shield and for heating elements.
Properties of tungsten - tungsten alloys
- an extremely high melting point (3420°C) – the highest of all metals – while also having a low vapor pressure (at 2000°C < 4 ∙ 10-9 Pa)
- a high modulus of elasticity
- good thermal resistance at a low coefficient of thermal expansion
- a high density of 19.3 g/cm³ (at 20 °C)
- good chemical resistance against inorganic acids, alkaline solutions, organic acids, non-metals, glass without oxidizers, glass melts, and gases
- high corrosion resistance against metal melts
Machining tungsten - tungsten alloys
- at 1 mm thickness 300 – 400 °C
- at 4 mm thickness 600 – 700 °C
- at 7 mm thickness 650 – 800 °C
- at 1 mm thickness 400 – 500 °C
- at 4 mm thickness 850 – 950 °C
- at 7 mm thickness 950 – 1000 °C