This is a view of transgranular attack. This is a 304L stainless steel and was caused from chloride. This is known as (CSCC) or Chloride Stress Corrosion Cracking. Magnification of photo is approximately 50X.
This is another view of Transgranular Cracking also CSCC. This type of corrosion cracking is very fast acting. The reaction time for contamination to travel through grains structures and not around the boundaries is why this type of corrosive attack is so dangerous, and can lead to catastrophic failures. The cracking is not just isolated to the base material, but can be in a weld as well.