An investigation of 20Kh13 steel axial-compressor blade fractures

In most cases the initial crak in service of blades originates on the leading or trailing edges of the blade in the presence of production or technological defects. The purely fatigue zone of failure has a secondary source of failure which subsequently becomes the main crack.The character of failure of samples cut from the butt end portion of blades which failed at ‑40 to +20°C is similar to the character of failure of failed blades operating at reduced temperatures.In the portion of the blade near the root, submicrovoids and microcracks orginate after a service life of ∼30,000 h and accumulate after 45,000–50,000 h.The character of failure of axial-compressor blades in full-scale tests on a stand under severe conditions is similar to the character of blade failure with overloads under service conditions. In most cases the initial crak in service of blades originates on the leading or trailing edges of the blade in the presence of production or technological defects. The purely fatigue zone of failure has a secondary source of failure which subsequently becomes the main crack. The character of failure of samples cut from the butt end portion of blades which failed at ‑40 to +20°C is similar to the character of failure of failed blades operating at reduced temperatures. In the portion of the blade near the root, submicrovoids and microcracks orginate after a service life of ∼30,000 h and accumulate after 45,000–50,000 h. The character of failure of axial-compressor blades in full-scale tests on a stand under severe conditions is similar to the character of blade failure with overloads under service conditions.