The phrase "a key material in" is correct and usable in written English.
It can be used when discussing the importance or significance of a particular material in a specific context, such as in manufacturing, construction, or research.
Example: "Steel is a key material in the construction of skyscrapers due to its strength and durability."
Alternatives: "an essential component in" or "a crucial element in".
They can form glass, porcelain, and clay, but they also readily conduct electricity and are a key material in many high-tech electronics.
Copper, a key material in the construction industry which has risen 60% since last June, touched nearly $10,000 a tonne yesterday.
Demand for copper — a key material in construction and manufacturing — has long been a proxy for the overall health of the world economy.
A programming community called Element 14 – the atomic number of silicon, a key material in chips – has a large Raspberry Pi group, and so far there have been 30,000 downloads of the operating system software for the device, an order of magnitude more than have actually been made.
Grey brick is a key material in Chinese traditional architecture.
Silicon is a key material in many industrial sectors as metallurgy, electronics, and photonics.
A key material element in these negotiations is the breast pump, which in many ways has transformed how middle-class Chinese women address expectations about and ambitions to breastfeed their babies.
The simple form in question employs a so-called hindered settling factor (a key material property in suspension rheology) that is taken to be a straight-line function of the solids fraction.
Shortly thereafter, his recording career was interrupted by the 1942 44 musicians' strike and the diversion of shellac (a key material used in the manufacture of the then-standard ten-inch 78 rpm phonograph record) for the U.S. war effort during World War II.
NaOCl in our proposed technique is a key material for growing in situ oxide masking layer on monocrystalline silicon (c-Si) surface during etching in NaOH NaOCl bath.
Metal-polymer composites were studied as a key material for transistor construction in electronics industry[6].
