PSF27 is a tool steel produced using the Spray Forming Process. Spray forming—also known as spray casting or spray deposition—begins by melting an alloy steel in an induction furnace. The molten steel is then poured through a ceramic nozzle and broken up into droplets by an array of gas jets. The droplets are accelerated by the jets to impact onto a collection surface while still in a semi-solid condition. There they build up to form a spray-formed billet, assuming the shape of the substrate surface. The small size and rapid cooling of the droplets minimizes alloy segregation to produce an extremely fine-grained homogenous steel.
PSF27 consists of: