Magnesium alloys possess a unique combination of benefits stemming from their
exceptional strength-to-weight ratio and reduced density. The aforementioned
attributes render them notably attractive for utilization in automotive and
aeronautical sectors. Furthermore, these alloys are gaining significant interest
from the industry because of their outstanding dimensional stability, excellent
ability to dampen vibrations, high recyclability, and good castability. They
also exhibit superior stiffness, among other attributes. Nonetheless, magnesium
and its alloys face several noteworthy challenges that limit their industrial
utilization. These include low resistance to deformation over time, limited
stability at high temperatures, restricted malleability, poor ductility, and
inadequate resistance to corrosion. This study aims to investigate the
phenomenon of stress corrosion cracking in magnesium alloy when exposed to
potassium chromate. Addition of Ca showed better mechanical properties. A proof
ring test was conducted NaCl-K2CrO4 solution at 60% YS value of base material,
shows that the AZ91+4%Ca is having the least stress corrosion resistance.
Threshold stress for AZ91 with 1%, 2%, 3% wt% Ca is found to be higher than the
applied stress value in both the corrosion environment, so that the material has
not failed even after the test duration of 720h. The observed stress corrosion
resistance in AZ91+4% Ca is unsatisfactory due to the brittle nature of the
large Al2Ca phase. In contrast, AZ91 alloys containing 1%, 2%, or 3% Ca, which
have a lower proportion of Al2Ca phase, exhibit improved mechanical properties
and enhanced resistance to stress corrosion cracking (SCC).