According to this press release, engineers have developed a new hard aluminum alloy that is also resistant to the high radiation seen in space, which in turn could make this lighter-than-steel metal practical for spacecraft.
Making spacecraft from aluminium is one solution, as aluminium is a light yet strong material. Alloys help aluminium become harder via precipitation strengthening, but the radiation encountered in space can dissolve the hardening precipitates with potentially disastrous and fatal consequences for astronauts.
But the research carried out at MIAMI-2 in partnership with Montanuniversitaet Leoben (MUL) in Austria has discovered that a particular hardening precipitate of a new aluminium alloy – developed by a group of metallurgists led by Professor Stefan Pogatscher (MUL) – does not dissolve when bombarded with particle radiation when compared with existing data on irradiation of conventional aluminium alloys.
If I understand this, traditional aluminum alloys have not been useful for building spacecraft because they cannot withstand the radiation of space. This alloy appears to solve this problem.
I would be interested in hearing what the space engineers in my readership think.