The creep performance of a domestic high⁃temperature incoloy 800HT alloy was tested using the small punch creep test technique.The CWA small punch creep test conversion method

and the EFS and MCH conversion methods were used respectively.The results of the uniaxial creep tests were compared with the small punch creep test results.The results show that

for small punch creep test data of 800HT alloy

the CWA method outperforms the EFS and MCH conversion methods.When fitting the uniaxial creep data

the Wilshire founction

which takes into account the creep activation energy in the yield state

correlates well with the 800HT creep data.With the small punch creep test technique

the requirements for determining the high temperature creep properties of the domestic 800HT alloy can be met.