Method for Measuring Elastic Modulus of Pipe Coating

Abstract

The invention discloses a method for measuring elastic modulus of a pipe coating. The method comprises the following steps that the elastic modulus Es of matrix of a composite sample to be measured is measured by a gap-ring method; the composite sample to be measured is processed to a gap-ring sample, the gap is formed in the middle of the sample height, and the gap-ring sample of the composite sample is compressed and loaded, the increasing amount of the load delta P and the variable quantity of the compression displacement delta Delta within the online elastic range are recorded; the derived analytic expression of Es, delta P, delta Delta and alpha is used to calculate the ratio alpha of the coating elastic modulus Ec and the matrix elastic modulus Es, and then the coating elastic modulus Ec is obtained according to the equation Ec=alpha*Es. The method is simple in operation, convenient and efficient, and has great practical value and broad application prospect in the engineering field of pipe coating surface technology.

Description

technical field

[0001] The invention relates to the technical field of coating mechanical property measurement, in particular to a method for measuring the elastic modulus of a pipe coating. Background technique

[0002] In recent years, due to special requirements, a large number of pipes need to serve in various extreme environmental conditions, such as oxidation, corrosion, wear, high temperature and high pressure. Especially in corrosive environments, pipes are required to be resistant to corrosive industrial gases, industrial solutions, high-temperature molten salts, etc. under service conditions, so corrosion-resistant coatings are widely used in such pipes. And some pipes must meet certain functional requirements during service. For example, the selective absorption coating in the vacuum heat collecting tube must meet the requirement of high absorption rate of solar radiation in order to improve the heat collection efficiency of the vacuum heat collecting tube. In or...

Examples

Embodiment 1

[0090] Embodiment 1: Measurement of elastic modulus of outer coating

[0091] On the basis of obtaining the elastic modulus of the matrix above, the following steps are also included:

[0092] 1) Remove the inner surface of C-SiC and the upper and lower ends of the coating by grinding to obtain the outer coating of the C-SiC pipe coating sample, and then use a diamond blade to cut a gap with a width of about 2 mm to form a gap ring sample;

[0093] 2) Use a micrometer to measure the outer diameter R of the notched ring sample c = 15.10mm, inner diameter r = 11.95mm, width b = 7.16mm; using a digital microscope to measure the coating thickness h = 36μm; then the outer diameter of the substrate R = Rc-h = 15.064mm;

[0094] 3) Place the notched ring sample with the outer coating on the support table of the universal testing machine, and keep the notch at 1 / 2 of its height, and compress the sample at a loading rate of 0.1mm / min, The compression displacement variation of the no...

Embodiment 2

[0096] Embodiment 2: Measurement of elastic modulus of inner coating

[0097] 1) Remove the outer surface of C-SiC and the coating at the upper and lower ends by cutting to obtain a C-SiC pipe coating sample with an inner coating. Use a polishing machine to polish the surface, and then use a diamond blade to cut out a A notch with a width of about 2 mm to form a notched ring sample;

[0098] 2) Use a micrometer to measure the outer diameter of the notch ring sample R = 15.10mm, inner diameter rc = 11.95mm, width b = 7.14mm; use a digital microscope to measure the coating thickness h = 83μm; then the inner diameter of the substrate r = r c +h=12.033mm;

[0099] 3) Place the notched ring sample with the outer coating on the support table of the universal testing machine, and keep the notch at 1 / 2 of its height, and compress the sample at a loading rate of 0.1mm / min, The compression displacement variation of the notched ring sample between 4N and 10N (△P=6N) was measured by a h...

Embodiment 3

[0101] Embodiment 3: the measurement of elastic modulus of double-sided coating

[0102] 1) Remove the upper and lower coatings of C-SiC by grinding to obtain a double-sided coated C-SiC pipe coating sample, and then use a diamond blade to cut a gap with a width of about 2 mm to form a gap ring sample ;

[0103] 2) Use a micrometer to measure the outer diameter R of the notched ring sample c = 15.10mm, inner diameter r c = 11.95mm, width b = 7.14mm; using a digital microscope to measure the outer coating thickness h1 = 28μm, the inner coating thickness h 2=36μm; then the outer diameter of the substrate R=R c -h1=15.072mm, base inner diameter r=r c + h 2 =11.986mm;

[0104] 3) Place the notched ring sample with the outer coating on the support table of the universal testing machine, and keep the notch at 1 / 2 of its height, and compress the sample at a loading rate of 0.1mm / min, The compression displacement variation of the notched ring sample between 4N and 10N (△P=6N) w...

technical field

[0001] The invention relates to the technical field of coating mechanical property measurement, in particular to a method for measuring the elastic modulus of a pipe coating. Background technique

[0002] In recent years, due to special requirements, a large number of pipes need to serve in various extreme environmental conditions, such as oxidation, corrosion, wear, high temperature and high pressure. Especially in corrosive environments, pipes are required to be resistant to corrosive industrial gases, industrial solutions, high-temperature molten salts, etc. under service conditions, so corrosion-resistant coatings are widely used in such pipes. And some pipes must meet certain functional requirements during service. For example, the selective absorption coating in the vacuum heat collecting tube must meet the requirement of high absorption rate of solar radiation in order to improve the heat collection efficiency of the vacuum heat collecting tube. In or...

Examples

Embodiment 1

[0090] Embodiment 1: Measurement of elastic modulus of outer coating

[0091] On the basis of obtaining the elastic modulus of the matrix above, the following steps are also included:

[0092] 1) Remove the inner surface of C-SiC and the upper and lower ends of the coating by grinding to obtain the outer coating of the C-SiC pipe coating sample, and then use a diamond blade to cut a gap with a width of about 2 mm to form a gap ring sample;

[0093] 2) Use a micrometer to measure the outer diameter R of the notched ring sample c = 15.10mm, inner diameter r = 11.95mm, width b = 7.16mm; using a digital microscope to measure the coating thickness h = 36μm; then the outer diameter of the substrate R = Rc-h = 15.064mm;

[0094] 3) Place the notched ring sample with the outer coating on the support table of the universal testing machine, and keep the notch at 1 / 2 of its height, and compress the sample at a loading rate of 0.1mm / min, The compression displacement variation of the no...

Embodiment 2

[0096] Embodiment 2: Measurement of elastic modulus of inner coating

[0097] 1) Remove the outer surface of C-SiC and the coating at the upper and lower ends by cutting to obtain a C-SiC pipe coating sample with an inner coating. Use a polishing machine to polish the surface, and then use a diamond blade to cut out a A notch with a width of about 2 mm to form a notched ring sample;

[0098] 2) Use a micrometer to measure the outer diameter of the notch ring sample R = 15.10mm, inner diameter rc = 11.95mm, width b = 7.14mm; use a digital microscope to measure the coating thickness h = 83μm; then the inner diameter of the substrate r = r c +h=12.033mm;

[0099] 3) Place the notched ring sample with the outer coating on the support table of the universal testing machine, and keep the notch at 1 / 2 of its height, and compress the sample at a loading rate of 0.1mm / min, The compression displacement variation of the notched ring sample between 4N and 10N (△P=6N) was measured by a h...

Embodiment 3

[0101] Embodiment 3: the measurement of elastic modulus of double-sided coating

[0102] 1) Remove the upper and lower coatings of C-SiC by grinding to obtain a double-sided coated C-SiC pipe coating sample, and then use a diamond blade to cut a gap with a width of about 2 mm to form a gap ring sample ;

[0103] 2) Use a micrometer to measure the outer diameter R of the notched ring sample c = 15.10mm, inner diameter r c = 11.95mm, width b = 7.14mm; using a digital microscope to measure the outer coating thickness h1 = 28μm, the inner coating thickness h 2=36μm; then the outer diameter of the substrate R=R c -h1=15.072mm, base inner diameter r=r c + h 2 =11.986mm;

[0104] 3) Place the notched ring sample with the outer coating on the support table of the universal testing machine, and keep the notch at 1 / 2 of its height, and compress the sample at a loading rate of 0.1mm / min, The compression displacement variation of the notched ring sample between 4N and 10N (△P=6N) w...

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