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peterh
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Liquid oxygen is not corrosive in the traditional sense. There is no electro chemical attack.

It can make many material must easier to ignite. For a fire or explosion to occur, all three parts of the fire triangle must be present. Oxygen is one, fuel is another (metals, plastics, actual propellants) and an ignition source.

Ignition source can be the traditional source, like spark, direct heat, or from particle impact (debris hitting a piece of metal or plastic and imparting enough energy to cause ignition) adiabatic compression (oxygen itself rapidly slowed by closing a valve, turning a corner), and others.

Metals and plastics all will burn to a certain extent depending on pressure, temperature, and chemical composition. Materials can be perfectly acceptable at some conditions and completely unuseable at others. The higher the pressure/ temperature the more likely that and ignition event can occur.

In general, materials fabricated from copper are the best but tend to be lower In stregnth and not high temperature. These include brass, copper, monel, tougmet. However, even these will burn in the conditions, but due to the high thermal conductivity can cool rapidly. They also do not become brittle in cold temperatures. Many of these will not burn until pressures are near 10000 psi.

Nickel based allows are the next likely material used, if off the shelf materials are being used, they are high in strength but can redily burn above 800 or so psi. Sometimes coating are used to help with ignition, but Inconel 718, Inconel 625 and others can ignite at pressures less than 1000 psi.

Carbon steel is never used, as it's easily ignited, becomes brittle at these temperatures.

Materials like titanium can ignite even at room temperature and aren't used.

Material like raw aluminum can also ignite at low pressures, 25 psi. But add anodization and aluminum is often used on the low pressures suction side of the pump.

On the high pressure dischrage side aluminum is not typically used as risk is to great of an issue.

Many rocket companies develop custom alloys to deal with issues.

Like all things in engineering, there is not just one material that will work, everything is configuration dependent.