Haynes25 (L-605) is a common heat resistant alloy used in mono-propellant structures and in screen materials for catalyst beds. The lifetime requirements for thrusters have expanded dramatically after studies conducted in the 1970s on mono-propellant materials used for achieving a long life. The material design had not changed for a long time, and L-605 was still used as thruster material due to its good heritage. Some important degradation incidents were found in the test-unit break-up inspection after the thruster life tests. The Japanese research team focused on the L-605 degradations found on the catalyst bed screen mesh used for mono-propellant thruster. The team analyzed the surface of the wire material and the cross-section of the wire screen mesh used in the life tests. The investigation showed that the degradation was caused by nitriding L-605 component elements. The team also suggested the installation of a platinum coating on the material surface as a L-605 nitric degradation measure.