Glock Pistols are manufactured by the Austrian weapons manufacturer Glock which was founded by Gaston Glock.
Glock pistols use high-strength polymer materials on their frames. The polymer (Polymer2, a type of synthetic plastic) used in Glock pistols is corrosion resistant that exceeds the specifications of stainless steel.
When metals are exposed to extreme temperatures, they become brittle and prone to break easily. Polymers are immune to this and are tougher than steel, almost approaching the hardness of diamonds.