Welding Repair Method Researchof Blade Engine

Aeroengine blades belongs to the thin-walled parts easy to deformation, is the mostprone to failure, and to achieve high performance, high quality, therefore the investment ofmanpower, material resources and financial resources. Engine under the condition of thehigh pressure high temperature, titanium alloy or high temperature alloy materials areneeded to manufacture blades, in order to meet the reliability of the engine, the life of theindicators, engine blades must have precise size, and the shape of the complete.The current our country for blade tip repair mainly adopts surfacing, namely firstsurfacing on suitable material, grinding to the required blade height, but in practice there isa difficulty: because in the process of welding, cannot use water cooling, direct causesecondary pollution splash blade, so at the time of welding temperature control is moredifficult. Temperature not too high, the cooling speed cannot too fast, or in the weldingseam and heat affected zone with crack. Due to welding temperature is too high, on thesurface of blade form oxide oxidation film, affect the use. Due to the rapid changes intemperature, also can produce stress. The organization of the local grain change, leading tothe change of the thermodynamic performance and mechanical properties of the blade,seriously affected the normal use of the plane. So the blade of aircraft engine repair, makeits basically restored to its original mechanical properties, and can be enough strength andtoughness to bear the mission, is a very economic saving.This paper studies the main contents are: blade welding process, the specificoptimization design. For ordinary blade welding process in the simulation of thetemperature field, stress field. Using flexible fixture, and cooled by argon weldingsimulation of temperature field, stress field of the blade. Discussion using argon gascooling mode for blade crystal organizational change. Under the aegis of the flexibleclamping is studied, and the cooling solutions for the influence of stress field.Through experimental research, using adaptive flexible clamping method, can be more effective to complete the need for repair welding blade, can achieve fixation, preventoxidation slag splash. TC4titanium alloy in the tip of drier with moving heat source andmoving to the left, the argon gas cools, blade in a relatively short period of time can reachthe temperature range of safety, greatly reduce the grain growth time, strength of materialscan be effectively improved. Stress field distribution increases along with the change oftime, focus on the blade tip. Adopt the method of argon gas cooling can increase thewelding stress to a certain extent.