Amorphous and semi-amorphous plastics are less resistant to chemical attack and environmental stress cracking because they lack a crystalline structure.
12.
Also mechanical properties are changed : stress cracking resistance and toughness in the cold rise, whereas yield stress and heat resistance decrease.
13.
One of these chemical reactions involves hydrogen sulfide in sulfide stress cracking ( SSC ), an important process for the oil and gas industries.
14.
Considering the inertia and kinetic energy of fuel in a plastic tank being transported by a vehicle, environmental stress cracking is a definite potential.
15.
Environmental stress cracking is defined as external or internal cracking in plastic induced by applied tensile stress less than its short-term tensile strength.
16.
In addition to being toxic, hydrogen sulfide in the presence of water also damages piping and other equipment handling sour gas by sulfide stress cracking.
17.
The drying out of the surface layers would lead to a volume contraction; the hydrated inner layers resist this contraction, leading to surface stress cracking.
18.
It also restricts the materials that can be used for piping and other equipment for handling sour gas, as many metals are sensitive to sulfide stress cracking.
19.
Some of the methods are vaporization, melt and blow, melt blow and burn, thermal stress cracking, scribing, cold cutting and burning stabilized laser cutting.
20.
Electron Beam processing of thermoplastic material results in an array of enhancements, such as an increase in tensile strength, and resistance to abrasions, stress cracking and solvents.
