| 摘要 |
1294705 Making aerofoil section blades; welding by pressure NORTH AMERICAN ROCKWELL CORP 12 Oct 1970 [5 Jan 1970] 48441/70 Headings B3A and B3R In making a metal turbine, compressor or fan blade an assembly comprising a plurality of rib elements and a spacer or spacers of a material different from that of the rib elements between adjacent rib elements and two cover plates between which the rib elements and spacers are sandwiched is disposed between dies in a cavity, apart from recesses to receive excess metal, having the shape and size of the blade to be formed, the assembly having a volume equal to or greater than the volume of the cavity apart from the recesses and the assembly being heated and pressure applied thereto to effect diffusion sounding between the cover plates and rib elements, the spacers being subsequently removed to provide a lightening hole or holes. A turbine, compressor or fan blade is formed by arranging a lower cover plate 38 in a cavity 32 in a female die 30, placing rib elements 40 on the plate 38 with leading and trailing edge elements 44, 46, placing a rod like spacer element 42 of circular, square &c. section between each pair of rib elements and placing an upper cover plate 48 on the rib elements. A fin 24 is provided in a recess in the die 30 to engage the lower cover plate 38, a fin 26 is provided to engage plate 48 and base 12 and flange members 14, 16 are also arranged to contact the end of the blade assembly. A male die 28 is then located in the cavity 32 of the female die, the assembly is enclosed by a thin walled retort 50, a vacuum pump is connected to a conduit 52 in the retort and the assembly is heated while under pressure. If the plates and rib elements are of titanium and the spacers of steel heating at 1600‹ F. under 2000 p.s.i. for several hours is employed. The blade is cooled and the steel spacers are leached by acid from the blade leaving lightening holes, the titanium surface being chemically etched to remove steel interaction products. The plates and rib elements may be of stainless steel or columbium and a thin interleaf or eutectic former may be employed. |
