| 摘要 |
1321045 Welding by fusion; making pistons; casting metals ASSOCIATED ENG Ltd 19 April 1971 [21 Jan 1970] 59869/69 Addition to 1254697 Headings B3A B3F and B3R [Also in Division F2] A piston is reinforced in the region of the or each gudgeon pin bore 4 by a filamentary reinforcement of fibres of carbon, tungsten carbide, silicon nitride or silicon carbide. In the piston shown in Figs. 1 and 2, carbon fibre filaments 11 extend from the crown 1 through webs 8 supporting the gudgeon pin bosses and around the gudgeon pin bore 4. A mandrel 12, Fig. 3, is coated with a salt solution to form a parting layer which is plasma sprayed with aluminium. Successive layers of nickel coated carbon fibre filaments 11 are wound on the mandrel, each layer being sprayed after winding with aluminium 13. The composite of carbon fibres, nickel and aluminium is then cut to the required axial length and parted at 14 to provide the reinforcement which is hot pressed to remove porosity. The reinforcements are preferably cast in the piston but alternatively, may be inserted in slots in the piston and electron beam welded, vacuum brazed or otherwise bonded to the piston body. The reinforcements may also be formed by surrounding the filaments with powdered material and sintering the powder or, alternatively, by hot pressing fibres coated with metal. In a further method, molten metal incorporating the fibres is cast and the casting then extruded. In modifications Figs. 6-8 (not shown), the reinforcements are arranged as described in Figs. 6-8 of the parent specification. |
