Nimocast 713 is the investment-casting grade in Henry Wiggin & Co's Nimocast series, the cast counterpart to the wrought Nimonic family developed for British gas-turbine work. It cross-references to AMS 5391A, the DIN designation G-NiCr13Al6MoNb (the aluminum figure is 6%, not the 16% sometimes seen on corrupted legacy data sheets - a genuine 16% aluminum nickel alloy would not be metallurgically sensible), BS HC203, and AFNOR NC13AD. Compositionally it sits in the same family as the internationally better-known Inconel 713C (UNS N07713): roughly 13.5% chromium, 6% aluminum, 4.5% molybdenum, and just under 1% titanium in a nickel matrix, with niobium and boron/zirconium micro-additions (not independently confirmed in this record) typically used to control grain-boundary strength in the cast structure.

The aluminum and titanium content precipitates the gamma-prime (Ni3(Al,Ti)) phase that gives this alloy its high-temperature strength, while chromium provides oxidation resistance. As an investment-cast, precipitation-hardened superalloy, Nimocast 713 was used for small-to-medium gas-turbine blades, vanes, and other hot-section components where the equiaxed or directionally solidified cast grain structure is acceptable for the service life required.

Nimocast 713 carries the full set of difficulties typical of cast, gamma-prime-strengthened nickel superalloys, and the as-cast microstructure makes it noticeably tougher on tooling than a wrought bar of similar composition. Coarse, dendritic cast grains, occasional carbide segregation at grain boundaries, and a harder, less homogeneous surface skin all act as abrasive, edge-chipping hazards that a wrought Nimonic bar simply does not present. Low thermal conductivity concentrates cutting heat at the tool-chip interface rather than letting it escape into the chip, accelerating crater wear, while the alloy's retained strength at elevated temperature means the tool gets no relief from softening as speeds increase.

Work hardening is aggressive: any rubbing, hesitation, or light interrupted cut work-hardens the surface layer and makes the next pass dramatically harder to cut. A constant, adequate chip load that stays below the previously deformed layer is essential. Nimocast 713 also galls and builds up on cutting edges readily due to its chemical affinity for tool materials. Rigid setups, sharp positive-rake coated carbide grades suited to cast superalloys, conservative speeds relative to wrought equivalents, and heavy, consistent coolant delivery are the standard countermeasures - expect shorter tool life than the same nominal alloy in wrought form.