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CN-116817810-B - Thickness measuring method for single crystal hollow working blade

CN116817810BCN 116817810 BCN116817810 BCN 116817810BCN-116817810-B

Abstract

The invention discloses a thickness measuring method of a single crystal hollow working blade, which comprises the following steps of manufacturing a single crystal sample with a longitudinal parallel [001] crystal direction and a transverse deviation [100] crystal direction, wherein the deviation angle of the single crystal sample is 0 degree, 10 degrees, 20 degrees, 30 degrees and 45 degrees, performing reference correction on ultrasonic equipment by using the single crystal sample with the deviation angle of 0 degree, taking the ratio of the actual thickness to the test thickness of the single crystal sample with the deviation angle of 0 degree, 10 degrees, 20 degrees, 30 degrees and 45 degrees as an initial correction coefficient, extrapolating correction coefficient maps of different deviation angles of the single crystal hollow working blade within the range of 0-45 degrees by the initial correction coefficient, testing the secondary orientation of the single crystal hollow working blade, recording the numerical value, calculating the correction coefficient angle of a point to be tested by the secondary orientation, determining the corresponding correction coefficient of the deviation angle of the point to be tested in the correction coefficient maps, and multiplying the test thickness of the point to be tested by the correction coefficient to obtain the test thickness after the correction of the point to be tested. The invention solves the problem of large measurement error caused by ultrasonic thickness measurement orientation.

Inventors

  • YU JIAN
  • SHI JIA
  • LUO YUSHI
  • LI JIARONG
  • TAN JUNLONG

Assignees

  • 中国航发北京航空材料研究院

Dates

Publication Date
20260512
Application Date
20230703

Claims (8)

  1. 1. The thickness measuring method of the monocrystalline hollow working blade is characterized by comprising the following steps in sequence: Firstly, selecting a single crystal test bar which is homogeneous with a tested single crystal hollow working blade, and respectively manufacturing single crystal samples which are longitudinally parallel to the [001] crystal direction and transversely deviate from the [100] crystal direction by 0 DEG, 10 DEG, 20 DEG, 30 DEG and 45 DEG; Secondly, performing reference correction on ultrasonic equipment by using a single crystal sample with a longitudinal parallel [001] crystal direction and a transverse deviation [100] crystal direction by an angle of 0 DEG deviation; Thirdly, carrying out ultrasonic thickness measurement on single crystal samples with longitudinal parallel [001] crystal directions and transverse deviation [100] crystal directions at angles of 10 degrees, 20 degrees, 30 degrees and 45 degrees by using corrected ultrasonic equipment, comparing the test thickness obtained by ultrasonic test with the actual thickness to obtain the ratio of the actual thickness to the test thickness of the single crystal samples with longitudinal parallel [001] crystal directions, transverse deviation [100] crystal directions at angles of 10 degrees, 20 degrees, 30 degrees and 45 degrees, and taking the ratio of the actual thickness to the test thickness of the single crystal samples with longitudinal parallel [001] crystal directions, transverse deviation [100] crystal directions at angles of 0 degrees, 10 degrees, 20 degrees, 30 degrees and 45 degrees as initial correction coefficients respectively; Step four, extrapolated the correction coefficient map of different deviation angles of the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation within the range of 0-45 degrees through the initial correction coefficients of the deviation angles of 0, 10, 20, 30 and 45 degrees of the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation; Testing the secondary orientation of the single crystal hollow working blade by using orientation testing equipment, recording the numerical value of the secondary orientation of the single crystal hollow working blade, calculating the correction coefficient angle of a point to be tested on the single crystal hollow working blade by the secondary orientation, and determining the correction coefficient of the deviation angle of the point to be tested in correction coefficient maps of different deviation angles of the single crystal hollow working blade within the range of 0-45 degrees of longitudinal parallel [001] crystal orientation and transverse deviation [100] crystal orientation; And step six, carrying out ultrasonic thickness measurement on a point to be measured on the single crystal hollow working blade by using ultrasonic equipment, and multiplying the test thickness by a correction coefficient of the deviation angle of the point to be measured to obtain the corrected test thickness of the point to be measured of the single crystal hollow working blade, wherein the corrected test thickness is infinitely close to the real thickness.
  2. 2. The method for measuring thickness of a hollow single crystal rotor blade according to claim 1, wherein in the first step, the number of single crystal samples which are produced and have longitudinal parallel [001] crystal orientation and transverse deviation [100] crystal orientation of 0 °,10 °, 20 °, 30 ° and 45 ° is five, the heights of the five single crystal samples at each deviation angle are respectively 1mm, 2mm, 3mm, 4mm and 5mm, and the lengths and the widths of the single crystal samples are not less than 5mm.
  3. 3. The method for measuring thickness of a hollow single crystal rotor blade according to claim 2, wherein in the second step, the ultrasonic equipment is subjected to reference correction by using a single crystal sample with a longitudinal parallel [001] crystal orientation and a transverse deviation [100] crystal orientation by an angle of 0 ° and the method comprises the following steps in order: Using ultrasonic equipment to test five single crystal samples with the thicknesses of 1mm, 2mm, 3mm, 4mm and 5mm and the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation by 0 degree deviation angle, and respectively measuring the propagation time of sound waves between the two surfaces of the five single crystal samples in the thickness direction; Dividing the thicknesses of five single crystal samples which are longitudinally parallel [001] crystal orientation and transversely deviate from the [100] crystal orientation by corresponding propagation time to obtain propagation speeds of sound waves in the five single crystal samples respectively; And (3) averaging the propagation speeds of the sound waves in five single crystal samples which are longitudinally parallel to the crystal direction [001] and transversely deviate from the crystal direction [100] by 0 DEG, obtaining the average propagation speed of the sound waves which are longitudinally parallel to the crystal direction [001] and transversely deviate from the crystal direction [100] by 0 DEG, and inputting the average propagation speed which is longitudinally parallel to the crystal direction [001] and transversely deviate from the crystal direction [100] by 0 DEG into ultrasonic equipment, so that the reference correction of the ultrasonic equipment can be completed.
  4. 4. A method for thickness measurement of a single crystal hollow rotor blade according to claim 3, wherein in step three, the method for obtaining the initial correction coefficient comprises the following steps in order: Step A, carrying out ultrasonic thickness measurement on single crystal samples with the thicknesses of 1mm, 2mm, 3mm, 4mm and 5mm, which are longitudinally parallel [001] crystal orientation, transversely deviate from [100] crystal orientation by 10 degrees, 20 degrees, 30 degrees and 45 degrees, and obtaining the ratio of the actual thickness to the measured thickness of each single crystal sample; And B, respectively averaging the ratio of the actual thickness to the test thickness of each of five single crystal samples with the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation of 10 degrees, 20 degrees, 30 degrees and 45 degrees, and finally taking the average value of the ratio of the actual thickness to the test thickness of each single crystal sample with the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation of 0 degrees, 10 degrees, 20 degrees, 30 degrees and 45 degrees as an initial correction coefficient.
  5. 5. The method according to claim 4, wherein in the step B, the average value of the ratio of the actual thickness to the measured thickness of the single crystal sample having the longitudinal parallel [001] direction and the transverse deviation [100] direction of 0 °,10 °,20 °, 30 °, 45 ° is 1, 1.03, 1.07, 1.10, 1.14, respectively.
  6. 6. The method for measuring thickness of a single crystal hollow rotor blade according to claim 5, wherein in the fourth step, correction coefficient maps of different deviation angles in the range of 0-45 degrees of the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation of the single crystal hollow rotor blade are extrapolated, and the method comprises the following steps in sequence: Taking the deviation angles of single crystal samples which are longitudinally parallel to the crystal direction [001] and transversely deviate from the crystal direction [100] by 0 degrees, 10 degrees, 20 degrees, 30 degrees and 45 degrees as X axes, and taking the average value of the ratio of the actual thickness to the test thickness of the single crystal samples which are longitudinally parallel to the crystal direction [001] and transversely deviate from the crystal direction [100] by 0 degrees, 10 degrees, 20 degrees, 30 degrees and 45 degrees as Y axes; and b, obtaining correction coefficient maps of different deviation angles within the range of 0-45 degrees of longitudinal parallel [001] crystal orientation and transverse deviation [100] crystal orientation of the single crystal hollow working blade through fitting calculation.
  7. 7. The method according to claim 6, wherein in the step a, the spatial coordinates of the single crystal samples having the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation of 0 °, 10 °, 20 °, 30 °, 45 ° deviating angles are respectively [0 °,1], [10 °,1.03], [20 °,1.07], [30 °,1.10], [45 °,1.14].
  8. 8. The method for measuring thickness of a single crystal hollow rotor blade according to claim 7, wherein in the fifth step, the calculation formula of the correction coefficient angle is: when P >90 °, β=45° - α - (P-90 °) — -45 °; When P is less than or equal to 90 degrees, beta=45° -alpha-P- (45 ° -; wherein: Beta is the correction coefficient angle, namely, the normal line of the to-be-measured point on the single crystal hollow working blade forms an included angle with the [100] crystal direction and the [010] crystal direction respectively, and the minimum included angle is used as the correction coefficient angle, and the unit is degree; Alpha-secondary orientation angle, namely the included angle between the positive X-axis direction of the single crystal hollow working blade and the [100] crystal direction, with the unit being degree; And the unit of the included angle between the normal line of the point to be measured on the P-single crystal hollow working blade and the positive direction of the X axis is DEG.

Description

Thickness measuring method for single crystal hollow working blade Technical Field The invention belongs to the technical field of quality detection of single crystal hollow working blades, and particularly relates to a thickness measuring method of a single crystal hollow working blade. Background The integral structure of the single crystal hollow working blade of the aeroengine is divided into a blade body, a flange plate and a tenon, part of the blade also comprises a blade crown, the single crystal hollow working blade is longitudinally oriented in a direction of nearly [001], and the blade body is twisted and has a thinner wall thickness. The single crystal hollow working blade is one of the most important hot end components of the aero-engine, and the quality of the single crystal hollow working blade directly influences the service performance of the aero-engine. The wall thickness measurement of the single crystal hollow working blade is an important part of blade quality detection, and the wall thickness of the single crystal hollow blade is usually measured by adopting industrial CT detection, sectioning detection, ultrasonic detection and other modes at present. Each wall thickness measurement of the blade has advantages and disadvantages. The wall thickness of the single crystal hollow working blade is measured by adopting an industrial CT detection mode, and the method has the advantages of high precision, but has low measurement efficiency and high cost, and can have larger error for the measurement of the thickness smaller than 0.5 mm. The wall thickness of the monocrystalline hollow working blade is measured by adopting a sectioning detection mode, and although each position of the blade can be accurately detected, the sectioning detection belongs to destructive detection, the whole blade can be damaged, and the method is not suitable for 100% detection of the blade. The ultrasonic detection is an important detection method for measuring the polycrystalline material, has the advantages of high detection efficiency, low cost and the like, adopts an ultrasonic detection mode to measure the wall thickness of the monocrystalline hollow working blade, and needs a single standard sample to carry out ultrasonic correction on equipment. Because single crystals belong to anisotropic materials, the orientations of different thickness measuring points are different, and the sound velocity propagation is different, the ultrasonic detection has larger test error, the relative error reaches more than 10 percent, and the absolute deviation value of the measurement result is larger especially for the position with thicker thickness on the single crystal hollow working blade. Therefore, it is necessary to develop an ultrasonic thickness measuring method for monocrystalline hollow working blades based on crystal orientation, so as to solve the problem of large error existing in the current measurement of the wall thickness of monocrystalline hollow working blades by adopting ultrasonic detection technology. There are some documents in the prior art for ultrasonic thickness measurement of single crystal hollow blades, but there is no document for ultrasonic thickness measurement of single crystal hollow working blades. The invention patent with application publication number CN102927935A discloses an ultrasonic detection method for the wall thickness of a single crystal hollow blade, which comprises the steps of firstly manufacturing a special template for detection, marking detection points on the blade by using the special template for detection, connecting points to be detected which are positioned on each measurement section and are positioned on the same crystal growth direction into a straight line, extending the straight line to a blade tip, measuring the wall thickness of the blade tip part of the to-be-detected point along the growth direction by using a vernier caliper according to the principle that the sound velocity of a single crystal material along the growth direction is approximately the same, measuring the sound velocity of the blade tip part of the to-be-detected point along the growth direction by using an instrument, further obtaining the sound velocity of each to-be-detected point, and finally inputting the sound velocity of each to-be-detected point into a thickness gauge, thus obtaining the wall thickness value of each to-be-detected point. According to the technical scheme, when the wall thickness of the blade is measured by ultrasound, the ultrasonic correction is not carried out by adopting a sample with the longitudinal parallel [001] crystal orientation and the transverse deviation [100] crystal orientation being 0 degrees, and compared with the traditional industrial CT detection technology, the detection efficiency and the detection precision are improved, but the measurement error is still large because the factors of ultrasonic correction are not considered, and the requiremen