This standard is used for ultrasonic flaw detection of titanium and titanium alloy products with a cross-sectional thickness greater than or equal to 13mm. GB 5193-1983 Ultrasonic flaw detection method for titanium and titanium alloy products GB5193-1983 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Titanium and titanium alloy products
Ultrasonic flaw detection method
UDC669.295+669
.2955.002.6bZxz.net
:620.179.1
GB5193-85
Method of ultrasonic inspection for wrought titanium and titanium alloy products This standard applies to ultrasonic flaw detection of titanium and titanium alloy products with a cross-sectional thickness greater than or equal to 13mm. 1 General requirements
1.1 Purpose
Mainly used to detect internal defects, such as cracks, pores, looseness and other discontinuities in the exposed or unexposed surface tissue.
1.2 Method category
This standard specifies the use of longitudinal wave pulse reflection method for ultrasonic flaw detection. When necessary, the supply and demand parties may negotiate to use shear waves or other wave types. For example, for Φ13~70mm bars, shear wave flaw detection can be considered. Both water immersion method and contact method are acceptable. 1.3 Personnel
The operator should reach the level of non-destructive testing personnel at the ministerial level or the equivalent level of the third grade or above, and the personnel issuing and interpreting the inspection report should reach the level of personnel at the ministerial level or the equivalent level of the second grade or above. 1.4 Surface
1.4.1 The surface to be inspected should have a finish equivalent to v5. If processing is required, round-end tools should be used for processing or grinding. The surface should not have machined or polished particles, oil, grease, cutting compounds, etc. 1.4.2 The inspected product should have a common geometric cross-section, such as round, square, polygonal, etc. Flat products should ensure the straightness of each surface.
2. Flaw detection equipment
2.1 Flaw detector
The flaw detector shall comply with the requirements of JB1834-76 "Technical conditions for type A pulse reflection ultrasonic flaw detector". 2.2 Probe
2.2.1 Straight probes with a diameter of 12 to 32 mm and an operating frequency of 5 MHz are recommended for immersion flaw detection of flat products with a thickness of 20 to 230 mm, or for contact flaw detection of flat products or round products with a thickness of 70 to 230 mm. 2.2.2 Focused probes with a diameter of 6 to 16 mm and an operating frequency of 5 to 10 MHz are recommended for longitudinal wave divergent sound beam immersion flaw detection of round products with a diameter of 13 to 70 mm. 2.2.3 When both the supplier and the buyer agree, probes with a frequency lower than 2.25 MHZ or special types are allowed to be used. 2.3 Coupling agent
2.3.1 When testing by water immersion method, clean tap water can be used as coupling agent, and rust inhibitor or wetting agent can be added. There should be no visible bubbles in the water that may interfere with ultrasonic testing. 2.3.2 When testing by contact method, engine oil, glycerin, transformer oil, water glass, etc. can be used as coupling agent. 3 Comparison test block
3.1 The comparison test block should be made of titanium and titanium alloy materials with the same or similar acoustic properties and surface conditions as the product to be inspected. The change in its acoustic characteristics is required to be within ±25%. If it exceeds ±25%, necessary compensation correction should be made, and the correction method should be agreed by the user. 3.2 The processing technical conditions of the comparison test block should meet the requirements of Appendix A of this standard. 3.3 When inspecting flat products, a flat test block should be used; when inspecting curved products, a comparison test block with roughly the same geometric shape as the flaw detection surface should be used, and the difference should not exceed ±25% of the radius of curvature of the product to be inspected. 3.4 When calibrating longitudinal waves, a flat-bottomed hole is used as the reflector. The buried depth is determined according to the product's shape and section thickness "T" according to the values ​​in Table 1.
Inspected product
>26~50
Diameter of round product
Thickness of flat product
4 Flaw detection
>50~130
>50~130
>130~200
Flat bottom hole buried depth
T,T- 6.5,6.5
4.1 Before flaw detection, appropriate comparison test blocks should be used to calibrate the instrument so that the amplitude of the reflected signal of the artificial defect in the test block is within the range of 25% to 90% of the full screen height to ensure that the inspected product can be inspected according to the standard requirements. 4.1.1 Tube-type instruments should be preheated for more than 15 minutes before use, and solid electronic component instruments should be preheated for more than 10 minutes. Before calibration and inspection, there should be enough time for the water, reference block and product system to reach temperature stability. 4.1.2 Calibration inspection should be carried out before each flaw detection and after each shift change, and after 2 hours of continuous work. If the equipment status changes during the flaw detection, the equipment should be recalibrated immediately, and all products inspected since the last calibration should be rechecked.
4.2 When using the longitudinal wave flaw detection method for water immersion, adjust the incident angle of the sound beam so that the amplitude of the reflected signal on the incident surface reaches the maximum, thereby standardizing the incident angle of the longitudinal wave (straight beam flaw detection). When flaw detection, the change of the determined angle should be within ±2. 4.3 The determination of bottom wave loss should be carried out on the surfaces of the products to be inspected that are parallel to each other. Under the scanning sensitivity, when the average change value of the bottom reflection signal of the product to be inspected exceeds ±50% of the bottom reflection signal height recorded by the reference block, flaw detection cannot be carried out, and the product to be inspected must be processed as necessary to meet the flaw detection requirements. 4.4 The allowable background noise should not exceed 70% of the reflection height of the reference flat-bottom hole in the comparison test block. If the background noise exceeds these levels, the sections involved should be re-inspected comprehensively to ensure that the product meets the specified requirements. 4.5 The pulse repetition frequency during water flooding flaw detection shall not be less than 400Hz. 4.6 The scanning speed during flaw detection shall not be greater than the scanning speed that can distinguish the flat-bottom holes in the comparison test block. For manual scanning without an alarm system, the recommended scanning speed should not exceed 150mm/s. For manual or automatic scanning with an alarm system, the recommended scanning speed should not exceed 500mm/s. 4.7 The instrument control knob setting position and the parameters determined during calibration shall not be changed during product flaw detection. The pulse width is set to the minimum to provide appropriate resolution. 4.8 The inspection surface area shall comply with the provisions of Table 2 Table 2
Inspected products
Rods and forged parts
Forgings and extrusions
Parts
Section thickness
Rods, diameter 13~50
Rods, diameter greater than 50
Cakes, ring parts
Inspection area
Part of the circumference
The entire circumference
All surfaces
Two end surfaces
Specific circumstances shall be negotiated by both parties
Except for the end surfaces
Ring parts shall be subject to additional inspection of the outer side surfaces
Surfaces as required by the drawings and order sheets
Note: If transverse waves or refracted longitudinal waves are used instead of adjacent surface inspections, all flat products may be inspected on only one side or both sides. These inspections, calibrations and inspection parameters shall be determined by negotiation between the supply and demand parties. 4.9 When testing by immersion method, the best water path should be selected according to the probe and the metal sound path during the test. The change of water path during the test should be within ±6mm of the determined best water path. 4.9.1 The detection spacing used during detection should be 50% of the effective beam diameter. The effective beam diameter is determined by the following method: At the appropriate gain adjustment position, record the total distance of the transverse movement of the probe when a flat-bottomed hole with a small burial depth in the test block is detected. The signal amplitude attenuation within this distance is not more than 50%. 4.9.2 For distance-amplitude correction, it is recommended to use the electronic distance-amplitude correction method. If the minimum pulse signal amplitude meets the requirements of 4.1, the distance-amplitude curve drawn on the fluorescent screen can also be used. The curve is drawn using the distance-amplitude calibration test block. When the noise level does not mask the required reflection signal, the distance-amplitude calibration test block can be used for the highest sensitivity for testing and evaluated using the appropriate metal sound path. 4.10 When testing by contact method, the detection spacing should not be greater than the probe wafer diameter! Or the effective sound beam diameter! The latter is determined according to the requirements of 4.9.1. The smaller of the two is selected. 4.11 When performing water immersion or contact flaw detection, regional inspection can be carried out. In this case, each area should be calibrated separately.
The ultrasonic quality requirements for longitudinal wave flaw detection are divided into four levels as specified in Table 3. The applicable level should be specified in the material technical standard or order form.
Hole diameter of a single discontinuity
5.2 The reflection signal of any discontinuity point should not be greater than the reflection signal of the reference flat-bottom hole at the same depth as the discontinuity point.
5.3 Inspection of bottom wave loss. When the bottom reflection signal is compared with the same or similar defect-free products, there is a non-saturated bottom wave loss of more than 50%, and at the same time, there is an increase in the signal between the incident surface and the bottom surface (at least twice the normal background noise signal). At this time, the product is unacceptable. 5.4 Noise levels exceeding the provisions of 4.4 are unacceptable. 5.5 When using special comparison test blocks or standards not listed in Table 3 for inspection, the acceptance criteria shall be determined by negotiation between the supplier and the buyer.
Rejection and processing
If the reflected signal exceeds the determined standard, but the defect can be eliminated in the manufacturing process, such products can be determined by negotiation between the supplier and the buyer. All those that cannot be eliminated shall be rejected. Appendix A
Technical requirements for comparison test blocks
(Supplement)
A.1 The dimensions and tolerance requirements of the processed comparison test blocks are shown in the figure below. py±0.76
Dimensions and tolerances of comparison test blocks
Note: ①X is the metal sound path.
②When Y is 50mm, it is suitable for testing a depth range of less than 150mm; when Y is 64mm, it is suitable for a depth range of 150~300mm: when the testing depth is greater than 300mm, a larger diameter shall be used. ③a≤1.6mm, the deviation is ±0.013mma>1.6mm, the deviation is ±0.03mm. ④b≥3.2mm,h≥3.2mm.
Additional Notes:
This standard is proposed by China Nonferrous Metals Industry Corporation. This standard is drafted by Baoji Nonferrous Metals Processing Plant. The main drafters of this standard: Hu Shaoting, Zhao Fenglan. GB
516885
Supplement)
According to needs, part of Figure B1 to Figure B21 can be selected as the high and low magnification rating diagram of two-phase titanium alloy. The qualified limit is determined in the product technical conditions by negotiation between the supply and demand parties according to different alloys, processes, specifications and uses. Figure B1
GB5168-85
Macrostructure of grade 10 titanium blank
GB5168-85
Macrostructure of grade 20 titanium blank
Figure B3 Macrostructure of grade 30 titanium blank 1×GB516885
Figure B4 Macrostructure of grade 40 titanium blank 1x
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