Apparatus for material tests using an internal loading system in high-pressure gas at room temperature

Area of Science:

• Materials Science
• Mechanical Engineering
• High-Pressure Physics

Background:

• Conventional material testing equipment can be cumbersome for high-pressure gas environments.
• Accurate material property assessment under extreme conditions is crucial for safety and performance.

Purpose of the Study:

• To develop a new apparatus for material testing using an internal loading system in high-pressure gas.
• To evaluate the tensile properties of SUS316 stainless steel in hydrogen and argon environments.

Main Methods:

• Development of a high-pressure control system and pressure vessel with an internal piston-based loading mechanism.
• Direct measurement of specimen load using an external load cell and displacement using an external extensometer.
• Tensile testing of SUS316 stainless steel (JIS G4303) in 90 MPa hydrogen and argon at room temperature.

Main Results:

• The developed apparatus successfully conducted material tests in high-pressure gas without conventional equipment.
• SUS316 stainless steel exhibited significantly altered tensile properties in a hydrogen environment compared to argon.
• Evidence of hydrogen gas embrittlement was observed in the tested material.

Conclusions:

• The new apparatus is effective for material testing under high-pressure gas conditions.
• Hydrogen gas significantly impacts the tensile properties of SUS316 stainless steel, leading to embrittlement.
• Further investigation into hydrogen embrittlement mechanisms in materials is warranted.