Grey Iron to BS EN 1561: 1997
GM241 is a grade of Grey iron most commonly produced for the manufacture of Press Tools from Poly Patterns. It has a medium sized graphite microstructure and a matrix with a high pearlite content. It is a grade alloyed with Molybdenum and Chromium, enhancing tensile strength and hardeness when flame hardened after machining.
The alloys must be added at the correct percentages to ensure there is sufficient pearlite within the matrix. For Press Tool castings that are flame hardened, the process converts the highly pealitic structure into tempered martensite producing a casting that is encased in a very hard martensitic outer layer with a soft core.
GM241 has excellent impact, compression and load bearing properties making it excellent for castings such as Lift Pulley wheels when wear resistance and very high strength are of critical importance, though it finds the majority of its application in Press Tools for the automotive industry.
Grade analysis for GM241 castings can be using in house spectromer facilities or certifiied by an independent UKAS laboratory if preferred.