The effect of cerium on temper embrittlement of P-doped Mn structural
steels has been investigated by measurements of the ductile-brittle tr
ansition temperature and observations by AES, SIMS and SEM of the frac
ture surfaces of isothermally embrittled steels. It is shown that P ca
n bring about the temper embrittlement of Mn structural steels; cerium
may reduce the temper embrittlement of the steels and the segregation
of cerium to grain boundaries may play an important part in reducing
the temper embrittlement of the steels.