Integral thermal forming method of aero-engine flow guide pipe

The invention provides an integral thermal forming method of an aero-engine flow guide pipe. The integral thermal forming method comprises the following steps of filling low-melting-point tin alloy with specific components in a high-temperature alloy pipe in advance before prepressing, filling metal lead with the melting point higher than that of the tin alloy according to process conditions during hot pressing, ensuring that the forming characteristics of the tin alloy and a solid alloy pipe after lead solidification are close to those of a bar, and therefore, the forming qualification rate can be effectively improved; after each step of pressing is finished, the filled low-melting-point metal can flow out in a heating mode, the appearance effect and the forming quality of a product are not affected, and the tin alloy and the metal lead can be recycled. According to the method, secondary compression molding is adopted, molded parts are not welded, weld joints are avoided, the mechanical performance of the pa