BS EN 17393:2020 pdf free download – Thermal spraying一Tubular coating tensile test.
5.3 Specimen to be sprayed, preparation and coating
The preparation of the specimen to be sprayed as well as the spraying parameters, such as the spraying procedure, spray material, coating thickness, energy data, movement pattern, etc., shall be in accordance with the specifications for the spraying procedure of the corresponding workpiece, if any.
The rotating specimen to be sprayed shall be coated over the entire length of its outer surface. The temperature of the specimen to be sprayed shall under no circumstances exceed those values reached when spraying the corresponding workpiece, if any, which can occur particularly when applying coatings of larger thicknesses. The sprayed specimen shall be removed from the fixture and the central fixing screw shall be taken out. Then the specimen can be directly tested in a tensile testing machine using the same clamping devices as in the tensile adhesive strength test according to EN ISO 14916. See Figure 1 in Clause 4.
5.4 Determination of outer diameter
After spraying, and before the test, the outer diameter shall be measured in at least 3 points along the surface of the cylinder length of the spray specimen, where one section shall be on the junction between the base samples. For each measurement section, the diameter shall be measured rotated by 900, and the mean value shall be calculated.
The maximum diameter tolerance is ± 0,01 mm.
Only suitable instruments, which need to be calibrated and traceable to national standards, shall be used during measurement. They shall be capable of measuring the diameter with an accuracy of at least 0,01 mm.
5.5 Number of specimens to be tested
Three specimens, which have been coated in one spray cycle using identical process parameters, shall be tested.
6 Test procedure
The specimen, with attached clamping arrangement, is inserted torque-free and bending-free into the tensile testing machine and loaded in tension at a constant rate and shock-free until fracture occurs.
9 Test report
The following shall be documented in the test report for each specimen:
a) reference to this standard, i.e. EN 17393:2020;
b) inspection body, examiner, date;
c) material of the base samples;
d) specification of the spray material;
e) preparation of the base sample surface to be coated;
f) spraying procedure;
g) thickness of coating (tolerance: 土0,01 mm);
h) designation of specimen and diameter (Da and D; tolerance:土0,01 mm);
i) tensile strength in MPa for each single specimen as well as the averaged value of the three
specimens of a series;
j) standard deviation;
k) results of the metallographic inspection or reference to its report number.
An example of a test report is given in Annex A (informative).