| 摘要 |
A method of making a hollow article, for example, a hollow airfoil, from first and second preformed sections involves first forming a precursor fluid impermeable (seal) diffusion bond between opposing bonding surfaces. The precursor bond is formed by subjecting the assembled sections to coordinated pressure-time-temperature conditions where a first high external pressure is applied to reduce any gaps between the opposing bonding surfaces and then a second lower external pressure is applied to actually form the precursor diffusion bond with only limited distortion of one of the sections and no distortion of the other section. In a second step of the method, the precursor bonded sections are subjected to coordinated pressure-time-temperature conditions where a high external and high internal pressure are utilized to form a complete parent metal diffusion bond between the bonding surfaces without distortion of either section. An inflation step may be conducted concurrently or subsequently to the second diffusion bonding step where, during the inflation step, a high external and high internal pressure are utilized to remove any limited distortion of the affected section. <IMAGE> |
