The Fenso™ product line was developed to provide excellent long life performance in cold quenching operations. FENSO 90 is a premium high speed quench oil. FENSO 90 is formulated with a highly effective accelerator concentrate that is designed to provide long service life with dependable quench speed control, as well as excellent and consistent part cleanliness. FENSO 150 is a high speed cold quench oil that is recommended for carbon and alloy steels, where uniform hardness, good part cleanliness and dimensional stability are required.

Quenching normally refers to the controlled cooling of manufactured steel parts in a fluid to achieve desired metallurgical properties. A steel is quenched to increase it's hardness, strength and wear resistance. The process consists of heating and holding the steel at temperatures above 1200°C to disperse the carbon and alloying elements throughout the iron mass. At this temperature, the steel has an austenitic structure. If the steel is allowed to cool slowly, as in annealing, the structure is transformed to pearlite, a soft ductile mechanical mixture of ferrite and cementite. If the steel is cooled more rapidly, a harder martensitic structure is formed which consists of a solid solution of iron carbide in iron.

Maximum hardness can be imparted to all common tool and machinery steels by cooling them in a controlled and rapid manner from their initial annealing temperature (> 900°C). The hardness that is achieved varies directly with the carbon content and the quenching speed. The steel alloy content has no appreciable effect on the maximum attainable hardness, but higher alloy steels allow for the attainment of maximum hardness at slower cooling rates. The rate of cooling that just causes the steel to harden fully to martensite is known as the "critical cooling rate". A cooling rate slower than this will produce a mixture of martensite and other intermediate transformation products which lower the quality of the quenched steel.

     • Based on IVF Quench test time to 500°C