Method for determining allowable value of interlayer tensile stress design of airplane composite material

Abstract

The invention relates to the technical field of aircraft composite material interlayer tensile stress design, and provides a method for determining an allowable value of an interlayer tensile stress design of an airplane composite material, which comprises: 1, determining influence parameters including a B reference value coefficient, an environment, a laying proportion, a thickness, a corner radius joint thickness, a damage and a thermal cycle influence coefficient; 2, determining an interlayer tensile stress design allowable value calculation formula based on the B reference value; 3, determining a test matrix; 4, determining a test environment standard, an environmental influence test moisture absorption saturation determination standard, a thermal cycle influence test cycle index and temperature spectrum, and a test piece damage determination standard; 5, performing a test by referring to an ASTM D6415 test standard to obtain an interlayer tensile stress average value and a B reference value initial value; 6, calculating a B reference value and each influence parameter; and 7, calculating an interlayer tensile stress design allowable value. The method is high in accuracy, highin universality, low in test cost and high in test efficiency.

Description

technical field [0001] The invention relates to the technical field of interlayer tensile stress design of aircraft composite materials, in particular to a method for determining a design allowable value of interlayer tensile stress of aircraft composite materials. Background technique [0002] Composite materials have the advantages of high specific strength, high specific stiffness, strong designability, and fatigue resistance, and have been widely used in aerospace, vehicles, ships, mechanical engineering and other fields. In the field of civil aviation, the percentage of composite materials used in the weight of civil aircraft structures ranges from 22% for Airbus A380, to 50% for Boeing B787 and COMAC CR929, and then to 52% for Airbus A350XWB. Together with aluminum alloys, it has become the material of choice for modern large civil aircraft structures. With the continuous development of composite material design and manufacturing technology, integrated structural desi...

AI Technical Summary

Problems solved by technology

However, the existing test methods for determining the design allowable value of interlayer tensile stress of aircraft composite materials do not consider comprehensive factors, and do not optimize the number of test groups, the number of test pieces, and the size of test pieces in the test, resulting in interlayer tension. The calculation accuracy of the design allowable value of tensile stress is low, the test cost is high, and the test efficiency is low

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