Critical current densities of Sr0.6K0.4Fe2As2 superconductors estimated from AC susceptibilities

► Effect of Ag addition on SrKFeAs (122 type) superconductors are examined by the grained Bean model. ► Critical current densities and their temperature and field dependence in the grains Jcg and the link Jcℓ are estimated. ► The Jcℓ 's of Ag-added sample are field independent and 7-9 times larger.