Low Carbon-13%Cr martensitic stainless steels have been widely used for line pipe application because of
their high strength and excel1ent corrosion resistance in corrosive conditions. Recently, both laboratory and
field experiences related to cracking near fusion line of these steels weld joints in hot acid environments has
been published. Electrochemical analysis of weld joints are expected to be effective to understanding
crack mechanism. In this paper, electrochemical behavior of low C - 13%Cr weld joints was me'dSured
by using solution flow type micro-droplet cell. In this unique technique, a droplet with a diameter of
hundreds of micrometers is used as an electrochemical cell and this technique enables local electrochemical
measurements. Measurement of corrosion potentials and potentiodynamic polarization for HAZ portion of
weld joints were focused.