A method for measuring the ablation performance of flame-retardant materials based on laser ablation

Abstract

The present invention provides a method for measuring the ablation performance of flame-retardant materials based on laser ablation, belonging to the technical field of measuring the ablation performance of flame-retardant materials. The method for measuring the ablation performance of flame-retardant materials based on laser ablation provided by the present invention includes the following steps: under the condition of a predetermined ablation energy density, the flame-retardant material is laser-ablated along the thickness direction to obtain the flame-retardant material after ablation; according to the thickness change and mass change of the flame-retardant material before and after laser ablation, the ablation rate and ablation residue rate of the flame-retardant material under the condition of the predetermined ablation energy density can be obtained respectively. By adjusting the laser power density and laser emission time of laser ablation, the ablation performance law of the flame-retardant material under different ablation energy density conditions can be obtained, and the operation is simple, the test efficiency is high, and the time cost of the experiment is reduced. In addition, the present invention measures the ablation performance of the flame-retardant material based on laser ablation, and the experimental process is safe and reliable.

Description

Technical Field

[0001] The present invention relates to the technical field of measuring the ablation performance of flame retardant materials, and particularly relates to a method for measuring the ablation performance of flame retardant materials based on laser ablation. Background Art

[0002] At present, the oxygen-acetylene ablation test method is mainly used to evaluate the ablation performance of thermal insulation materials. Specifically, by measuring the thickness change, mass change of the specimen before and after ablation, and the temperature of the back wall of the specimen, parameters such as the linear ablation rate, mass ablation rate, and adiabatic index of the specimen can be obtained. When using the oxygen-acetylene ablation test method to test the ablation performance of thermal insulation materials, it is necessary to first ignite the flame, adjust the oxygen and acetylene flow rates. After the flame is stable, the heat flux density of the flame is measured using a water-cooled calorimeter, and its magnitude is controlled to be (4186±418.6) kW / m 2 , and then control the ablation gun to rotate to the position of the specimen in the water-cooled sample holder, perform ablation and start timing. After the ablation is completed, rotate the ablation gun away from the flame. In this method, the heat flux density needs to be adjusted by the flow rates of oxygen and acetylene, and it is difficult to obtain the quantitative relationship between the ablation rate and the ablation energy density. Moreover, the operation is complex and the test efficiency is low. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for measuring the ablation performance of flame retardant materials based on laser ablation. The present invention measures the ablation performance of flame retardant materials based on laser ablation, can obtain the quantitative relationship between the ablation energy density and the ablation rate, and has simple operation and high test efficiency.

[0004] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a method for measuring the ablation performance of flame retardant materials based on laser ablation, including the following steps:

[0006] Under the condition of a predetermined ablation energy density, the flame retardant material is subjected to laser ablation along the thickness direction to obtain the flame retardant material after ablation;

[0007] According to Equation I, the ablation rate of the flame retardant material under the condition of a predetermined ablation energy density is obtained:

[0008] d = d1 - d2 Equation I;

[0009] In Equation I, d is the ablation rate of the flame retardant material under the condition of a predetermined ablation energy density, d1 is the thickness of the flame retardant material, and d2 is the thickness of the flame retardant material after ablation;

[0010] According to Equation II, the ablation residue rate of the flame retardant material under the condition of a predetermined ablation energy density is obtained:

[0011] r = (m1 - m2) / m1 Equation II;

[0012] In Formula II, r is the ablation residue rate of the flame retardant material under the condition of a predetermined ablation energy density, m1 is the mass of the flame retardant material, and m2 is the mass of the flame retardant material after ablation;

[0013] The predetermined ablation energy density is obtained according to Formula III:

[0014] p = w·t, Formula III;

[0015] In Formula III, p is the predetermined ablation energy density, w is the laser power density of the laser ablation, and t is the laser emission time of the laser ablation.

[0016] Preferably, the device used for the laser ablation is a laser generator; when performing the laser ablation, the flame retardant material is placed directly below the collimator lens in the laser generator.

[0017] Preferably, the thickness of the flame retardant material is 0.5 - 2 cm.

[0018] Preferably, d1 is the thickness of the flame retardant material at the location irradiated by the laser beam during the laser ablation.

[0019] Preferably, d2 is the thickness of the ablated flame retardant material at the location irradiated by the laser beam after the laser ablation.

[0020] Preferably, the mass of the flame retardant material is 0.5 - 2.5 g.

[0021] Preferably, the thickness of the flame retardant material and the thickness of the ablated flame retardant material are measured using a thickness gauge, and the mass of the flame retardant material and the mass of the ablated flame retardant material are weighed using an electronic balance.

[0022] Preferably, the laser power density of the laser ablation is 10 - 30 W / m 2 .

[0023] Preferably, the laser emission time of the laser ablation is 0.5 - 2 s.

[0024] Preferably, the flame retardant material includes a flame retardant polyurethane material, a flame retardant polyethylene material, or a flame retardant polypropylene material.

[0025] The present invention provides a method for measuring the ablation performance of a flame retardant material based on laser ablation, comprising the following steps: under a predetermined ablation energy density condition, laser ablate the flame retardant material along the thickness direction to obtain the ablated flame retardant material; according to the thickness change and mass change of the flame retardant material before and after laser ablation, the ablation rate and ablation residue rate of the flame retardant material under the predetermined ablation energy density condition can be obtained respectively. The present invention measures the ablation performance of the flame retardant material based on laser ablation. By adjusting the laser power density and laser emission time of the laser ablation, the ablation performance law of the flame retardant material under different ablation energy density conditions can be obtained, and the operation is simple, the test efficiency is high, and the time cost of the experiment is reduced.

[0026] In addition, when using the oxy-acetylene ablation test method to test the ablation performance of the thermal insulation material, the ablation flame temperature during the test is about 3000 °C. If the personnel responsible for the control system and the personnel responsible for the loading and unloading work do not cooperate closely, it is easy to cause accidents such as burning of the face and arms due to the rotation of the ablation gun head. The present invention measures the ablation performance of the flame retardant material based on laser ablation, and the experimental process is safe and reliable. Detailed implementation mode

[0027] The present invention provides a method for measuring the ablation performance of a flame retardant material based on laser ablation, comprising the following steps:

[0028] Under a predetermined ablation energy density condition, laser ablate the flame retardant material along the thickness direction to obtain the ablated flame retardant material;

[0029] Obtain the ablation rate of the flame retardant material under the predetermined ablation energy density condition according to Equation I:

[0030] d = d1 - d2 Equation I;

[0031] In Equation I, d is the ablation rate of the flame retardant material under the predetermined ablation energy density condition, d1 is the thickness of the flame retardant material, and d2 is the thickness of the ablated flame retardant material;

[0032] Obtain the ablation residue rate of the flame retardant material under the predetermined ablation energy density condition according to Equation II:

[0033] r = (m1 - m2) / m1 Equation II;

[0034] In Equation II, r is the ablation residue rate of the flame retardant material under the predetermined ablation energy density condition, m1 is the mass of the flame retardant material, and m2 is the mass of the ablated flame retardant material;

[0035] Obtain the predetermined ablation energy density according to Equation III:

[0036] p = w·t Equation III;

[0037] In Formula III, p is the predetermined ablation energy density, w is the laser power density of the laser ablation, and t is the laser emission time of the laser ablation.

[0038] In the present invention, the flame retardant material preferably includes a flame retardant polyurethane material, a flame retardant polyethylene material, or a flame retardant polypropylene material. In the present invention, the flame retardant material is preferably in a sheet-like structure; specifically, the present invention uses a flame retardant material with a flat surface and a uniform thickness for laser ablation. In the present invention, the thickness d1 of the flame retardant material is preferably 0.5 to 2 cm, more preferably 0.5 to 1 cm; wherein, the d1 is specifically the thickness of the flame retardant material at the position irradiated by the laser beam during laser ablation; in the embodiments of the present invention, the thickness of the flame retardant material is specifically measured by a thickness gauge. In the embodiments of the present invention, the length and width of the flame retardant material are preferably 1 cm. In the present invention, the mass of the flame retardant material is preferably 0.5 to 2.5 g, more preferably 0.65 to 1 g. In the embodiments of the present invention, specifically, a flame retardant material with a flat surface and a uniform thickness is selected, the thickness d1 of the flame retardant material is measured by a thickness gauge, and the mass m1 of the flame retardant material is measured by an electronic balance.

[0039] After obtaining the flame retardant material, in the present invention, under the condition of a predetermined ablation energy density, the flame retardant material is laser ablated along the thickness direction to obtain an ablated flame retardant material. In the present invention, the equipment used for the laser ablation is preferably a laser generator; when performing the laser ablation, specifically, the flame retardant material is placed directly below the collimator lens of the laser generator. The present invention preferably sets the laser power density and the laser emission time of the laser generator, and then performs the laser ablation. In the present invention, the laser power density of the laser ablation is preferably 10 to 30 W / m 2 , more preferably 20 to 25 W / m 2 ; the laser emission time of the laser ablation is preferably 0.5 to 2 s, more preferably 1 to 1.5 s. According to the laser power density and the laser emission time of the laser ablation, the present invention can obtain the ablation energy density according to Formula III.

[0040] After obtaining the ablated flame retardant material, the present invention measures the thickness d2 and the mass m2 of the ablated flame retardant material. In the present invention, the d2 is specifically the thickness of the ablated flame retardant material at the position irradiated by the laser beam after laser ablation, that is, the d1 and the d2 are respectively the thicknesses of the flame retardant material corresponding to the position irradiated by the laser beam before and after laser ablation. In the embodiments of the present invention, specifically, the thickness d2 of the ablated flame retardant material is measured by a thickness gauge, and the mass m2 of the ablated flame retardant material is measured by an electronic balance.

[0041] After obtaining the thickness d1 of the flame retardant material and the thickness d2 of the flame retardant material after ablation, the present invention obtains the ablation rate of the flame retardant material under the condition of a predetermined ablation energy density according to Equation I. After obtaining the mass m1 of the flame retardant material and the mass m2 of the flame retardant material after ablation, the present invention obtains the ablation residue rate of the flame retardant material under the condition of a predetermined ablation energy density according to Equation II. To ensure the reliability of the test results, the present invention preferably obtains multiple groups of ablation rate and ablation residue rate data through repeated experiments, and then takes the average value as the final test result. By adjusting the laser power density and laser emission time of laser ablation, the present invention can obtain the laws of the ablation performance (i.e., ablation rate and ablation residue rate) of the flame retardant material under different ablation energy density conditions, with simple operation, high test efficiency, and reduced time cost of the experiment.

[0042] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0043] Example 1

[0044] The test object of this example is a flame retardant polyurethane material. The method for measuring the ablation performance of the flame retardant polyurethane composite material by laser ablation is as follows:

[0045] Prepare the flame retardant polyurethane composite material into a flame retardant sheet material with a length and width of 1 cm and a thickness d1 of 0.500 cm (measured by a thickness gauge) with a flat surface and uniform thickness. Weigh the flame retardant sheet material using an electronic balance and record the mass m1;

[0046] Place the flame retardant sheet material directly below the collimator lens of the laser generator, set the laser power density of the laser generator to 20 W / m 2 , and the laser emission time to 1 s, then the laser action energy density is 20 J / m 2 , and then emit laser for laser ablation to obtain the flame retardant sheet material after ablation;

[0047] Use a thickness gauge and an electronic balance to measure the thickness d2 and mass m2 of the flame retardant sheet material after ablation respectively; then the ablation rate d = d1 - d2 of the flame retardant sheet material under the energy density condition of 20 J / m 2 , and the ablation residue rate r = (m1 - m2) / m1;

[0048] Repeat the above steps 5 times, and take the average value of the obtained ablation rate and ablation residue rate results to obtain the flame retardant sheet material at 20 J / m2 The average ablation rate and the average ablation residue rate at the energy density, and the specific results are shown in Table 1.

[0049] Table 1 Ablation rate and ablation residue rate of the flame-retardant sheet material in Example 1

[0050]

[0051] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for measuring the ablation performance of a flame retardant material based on laser ablation, comprising the following steps: Under the condition of a predetermined ablation energy density, the flame-retardant material is laser-ablated along the thickness direction to obtain the flame-retardant material after ablation; the flame-retardant material is a flame-retardant polyurethane material, a flame-retardant polyethylene material or a flame-retardant polypropylene material; the laser power density of the laser ablation is 10-30 W / m 2 , and the laser emission time of the laser ablation is 0.5-2 s; Obtain the ablation rate of the flame retardant material under a predetermined ablation energy density condition according to Equation I: d = d1 - d2 Equation I; In Equation I, d is the ablation rate of the flame retardant material under a predetermined ablation energy density condition, d1 is the thickness of the flame retardant material, and d2 is the thickness of the flame retardant material after ablation; Obtain the ablation residue rate of the flame retardant material under a predetermined ablation energy density condition according to Equation II: r = (m1 - m2) / m1 Equation II; In Equation II, r is the ablation residue rate of the flame retardant material under a predetermined ablation energy density condition, m1 is the mass of the flame retardant material, and m2 is the mass of the flame retardant material after ablation; Obtain the predetermined ablation energy density according to Equation III: p = w·t Equation III; In Equation III, p is the predetermined ablation energy density, w is the laser power density of the laser ablation, and t is the laser emission time of the laser ablation.

2. The method according to claim 1, wherein The equipment used for the laser ablation is a laser generator; when performing the laser ablation, place the flame retardant material directly below the collimator lens in the laser generator.

3. The method according to claim 1, characterized in that, The thickness of the flame retardant material is 0.5 - 2 cm.

4. The method according to any one of claims 1 to 3, characterized in that The d1 is the thickness of the flame retardant material at the location irradiated by the laser beam during the laser ablation.

5. The method according to any one of claims 1 to 2, characterized in that, The d2 is the thickness of the ablated flame retardant material at the location irradiated by the laser beam after the laser ablation.

6. The method according to claim 1, characterized in that, The mass of the flame retardant material is 0.5 - 2.5 g.

7. The method according to claim 1, wherein The thickness of the flame retardant material and the thickness of the ablated flame retardant material are measured using a thickness gauge, and the mass of the flame retardant material and the mass of the ablated flame retardant material are weighed using an electronic balance.

Images