A method for evaluating a non-firing material

Abstract

The application provides an evaluation method of non-ignition material, which comprises the following steps: 1) processing a material to be tested to obtain a sample; 2) determining the Vickers hardness value of the sample; and 3) comparing the Vickers hardness value of the sample with a threshold value to evaluate the non-ignition material of the material to be tested. The method provided by the application can provide reliable data, accurately evaluate the non-ignition performance of the material, and meet actual needs.

Description

Technical Field

[0001] This invention relates to the field of materials testing, and more particularly to a method for evaluating non-sparking materials. Background Technology

[0002] Non-sparking materials are those that do not produce sparks (or embers) when subjected to mechanical forces such as friction or impact with hard objects like metal or stone. Since sparks are often generated when people walk on the ground or when objects move and collide, these sparks can become ignition sources for combustion and explosion under suitable external conditions. Therefore, non-sparking materials have become an indispensable part of explosion-proof buildings. Currently, non-sparking materials mainly include: 1) non-sparking metallic materials, such as copper plates and aluminum plates, with simple raw materials; 2) non-sparking non-metallic materials: mainly divided into non-sparking organic materials (such as asphalt, PVC flooring, epoxy flooring, etc.) and non-sparking inorganic materials (non-sparking mortar, terrazzo, etc.).

[0003] Existing non-sparking performance testing methods mainly rely on Appendix A of the "Code for Acceptance of Construction Quality of Building Ground Engineering," employing the friction method. This involves placing the sample on a grinding wheel rotating at a certain speed, applying a certain force, and rubbing it, observing whether any instantaneous sparks are generated during the test. However, due to limitations in testing equipment and test design, the samples typically need to have sufficient area and thickness to be used in the test in order to accommodate the grinding wheel and fixing device, thus restricting sample selection.

[0004] In practical applications of non-sparking materials, the main challenge lies in the selection of aggregates. While standards recommend using marble, dolomite, or other limestone for crushed stone, natural stone often contains impurities. A high concentration of impurities or hard inclusions can easily lead to substandard non-sparking performance in the finished product. Furthermore, aggregates are mostly granular or small-sized, irregular materials, which cannot meet the area requirements of current non-sparking tests, and the samples cannot be effectively fixed. Current methods for determining whether a material is non-sparking are no longer suitable, thus posing a risk to its use. Summary of the Invention

[0005] This invention provides a method for evaluating non-sparking materials. The method provided by this invention can provide reliable data and accurately evaluate the non-sparking performance of materials, thus meeting practical needs.

[0006] This invention provides a method for evaluating non-sparking materials, comprising the following steps:

[0007] 1) The material to be tested is processed to obtain a sample;

[0008] 2) The Vickers hardness value of the sample was measured;

[0009] 3) comparing the Vickers hardness value of the sample with a threshold value to evaluate the non-ignition material of the material to be tested.

[0010] According to the present application, whether two objects can produce sparks depends mainly on the surface hardness of the objects. The hardness of the material itself has a great influence on whether it has non-ignition performance. The material with a Vickers hardness value below the threshold value is suitable for use in non-ignition materials and aggregates. The present application provides an evaluation method for judging whether a particle, small-sized or irregular material that cannot meet the test conditions in the prior art is a non-ignition material. At the same time, it provides a reliable basis for the selection of non-ignition material aggregates, reduces the unqualified rate of finished products, and effectively saves costs.

[0011] According to the non-ignition material evaluation method provided by the present application, in step 1), the surface of the sample is flat and smooth; preferably, the material to be tested is polished to make the surface roughness of the test surface of the sample not greater than 0.8 μm.

[0012] According to the non-ignition material evaluation method provided by the present application, in step 2), the Vickers hardness value is calculated by using formula 1.

[0013]

[0014] In the formula, F is the test force, and the unit is N; d is the arithmetic mean of two diagonal lines, and the unit is mm.

[0015] According to the non-ignition material evaluation method provided by the present application, in step 2), the Vickers hardness value of the sample is determined at room temperature, and at least three test points are selected.

[0016] According to the non-ignition material evaluation method provided by the present application, in step 2), the Vickers hardness values of the test points are compared, and the maximum value is taken as the Vickers hardness value of the sample.

[0017] According to the non-ignition material evaluation method provided by the present application, the material to be tested includes particles, small-sized or irregular materials.

[0018] According to the non-ignition material evaluation method provided by the present application, the material to be tested does not contain iron products; preferably, when the material to be tested is an aggregate containing a plurality of mineral components, different mineral components are selected for hardness testing. In the present application, iron products are affected by components and belong to ignition materials. By testing the hardness of different mineral components, it can be ensured that the hardness of the material can be fully mastered.

[0019] According to the evaluation method of the non-ignition material provided by the application, in step 3), if the Vickers hardness value is less than the threshold value, the material to be tested is a non-ignition material; if the Vickers hardness value is greater than the threshold value, the material to be tested is an easy-ignition material.

[0020] According to the evaluation method of the non-ignition material provided by the application, in step 3), non-ignition material evaluation includes: when the Vickers hardness value of the material to be tested is less than 150, it is determined that the material to be tested is a non-ignition material and can be used for non-ignition material and / or non-ignition material aggregate; when the Vickers hardness value of the material to be tested is greater than or equal to 150, it is determined that the material to be tested is an easy-ignition material and cannot be used for non-ignition material and / or non-ignition material aggregate. In the application, through analysis of test data of 24 typical ground materials, it is found that the hardness of the material itself has a great influence on whether the material has the non-ignition performance, and the material with a Vickers hardness value below 150 is suitable for use in non-ignition material and non-ignition material aggregate.

[0021] The evaluation method of the non-ignition material provided by the application includes the following steps:

[0022] 1) Preparation of a sample:

[0023] Select a material to be tested, polish the material to be tested to obtain a sample, and the test surface of the sample is flat, smooth and free of pollution, and the surface roughness is not greater than 0.8 μm;

[0024] 2) Vickers hardness determination:

[0025] Determine the Vickers hardness value of the sample at room temperature, and randomly select at least three test points; for the material to be tested which is an aggregate containing a plurality of mineral components, select different parts, colors and crystal bodies as test points according to the sample, and take the maximum value of the determined Vickers hardness value as the Vickers hardness value of the material to be tested;

[0026] The Vickers hardness value is calculated by formula 1;

[0027]

[0028] In the formula, F is the test force, and the unit is N; d is the arithmetic mean value of two diagonal lines, and the unit is mm;

[0029] 3) Non-ignition material evaluation:

[0030] When the Vickers hardness value of the material to be tested is less than 150, it is determined that the material to be tested is a non-ignition material and can be used for non-ignition material and / or non-ignition material aggregate; when the Vickers hardness value of the material to be tested is greater than or equal to 150, it is determined that the material to be tested is an easy-ignition material and cannot be used for non-ignition material and / or non-ignition material aggregate.

[0031] The present application has at least the following beneficial effects: the present application provides an evaluation method for judging whether a particle, small size or irregular material that cannot meet the test conditions in the prior art is a non-ignition material. At the same time, it provides a guidance basis for the selection of non-ignition material aggregates, reduces the unqualified rate of finished products in the later stage, and effectively saves costs. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0033] Figure 1 The present application provides a Vickers hardness value-non-ignition performance relationship diagram. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present application more clear, the technical solutions in the present application will be described clearly and completely below. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0035] Unless otherwise specified in the examples, the techniques or conditions are carried out according to the techniques or conditions described in the literature in the art or according to the product instructions. Unless otherwise specified, the instruments used are conventional products that can be purchased through regular channels. The methods described are conventional methods unless otherwise specified, and the raw materials described can be obtained through public commercial channels unless otherwise specified. Unless otherwise specified in the examples, the techniques or conditions are carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0036] Example 1

[0037] This example provides an evaluation method for non-ignition materials, using Yun Dolagrey marble ore as non-ignition material aggregate, and the evaluation method is described.

[0038] (1) Cut the Yun Dolagrey marble ore into a sample of 25mm x 25mm x 18mm, and polish the test surface, with a surface roughness Ra of 0.54μm.

[0039] (2) Vickers hardness determination:

[0040] The Vickers hardness of the sample is measured at room temperature, and the test points are selected from different parts, colors and minerals of the ore test surface. The test adjustment is: t is 15 seconds, and F is 1 kg.

[0041] The hardness value HV of the sample is calculated by formula (1), and the maximum value is taken as the test result, as shown in the following table:

[0042] Table 1 Vickers hardness measurement data of Example 1

[0043] Test point 1 2 3 4 HV max HV value 136.3 138.4 134.3 132.6 138.4

[0044] (3) Evaluation of non-ignition material:

[0045] The Vickers hardness of Yun Du La gray marble is less than 150, and the material can be used for non-ignition material and aggregate.

[0046] The present application obtains the relationship between the Vickers hardness value (ordinate) and the non-ignition performance by analyzing the test data of 24 typical ground materials Figure 1 ), and judges by taking the Vickers hardness HV150 as the threshold. In the hardness measurement of the 24 typical materials: the materials with hardness values between 13.9 and 157.1 are tested by the original non-ignition performance test method (friction method), and no sparks are generated; the materials with hardness values above 157.1 are tested by the original non-ignition performance test method (friction method), and sparks are generated. Considering safety and the non-uniformity of the material, the Vickers hardness value 150 is selected as the threshold after verification.

[0047] Example 2

[0048] This embodiment provides an evaluation method of non-ignition material, taking red copper plate as non-ignition material, and explaining according to the evaluation method.

[0049] (1) Select a red copper plate sample with a size of 50mm*50mm*2mm, and polish the test surface, with a surface roughness Ra of 0.27μm.

[0050] (2) Vickers hardness measurement:

[0051] The Vickers hardness of the sample is measured at room temperature, and the test points are selected from different parts, colors and minerals of the ore test surface. The test adjustment is: t is 15 seconds, and F is 1 kg.

[0052] The hardness value HV of the sample is calculated by formula (1), and the maximum value is taken as the test result, as shown in the following table:

[0053] Table 1 Vickers hardness measurement data of Example 2

[0054] Test point 1 2 3 HV max HV value 95.7 101 98.3 101

[0055] (3) Evaluation of non-ignition material:

[0056] The Vickers hardness of the red copper plate is HV < 150, and the material can be used for non-ignition material.

[0057] Example 3

[0058] This example provides an evaluation method of non-ignition material, taking Yashi white marble ore as non-ignition material aggregate, and the evaluation method is described.

[0059] (1) Cut the Yashi white marble ore into a sample of 50mm x 50mm x 12mm, select a representative gray texture on the surface of the sample, and polish the test surface, with a surface roughness Ra of 0.42μm.

[0060] (2) Vickers hardness determination:

[0061] Determine the Vickers hardness value of the sample at room temperature, and test different parts, colors and minerals of the ore test surface as test points, with a test adjustment of t for 15 seconds and F for 1kg.

[0062] The hardness value HV of the sample is calculated by formula (1), and the maximum value is taken as the test result, as shown in the following table:

[0063] Table 1 Vickers hardness determination data of Example 1

[0064] Test point 1 2 3 4 5 HV max HV value Test point HV max HV value 220.8 184.5 139.5 181.6 199.4 220.8

[0065] (3) Evaluation of non-ignition material:

[0066] The Vickers hardness of the Yashi white marble is HV > 150, and the material cannot be used for non-ignition material and aggregate.

[0067] Comparative Example 1

[0068] The two materials (cloudy marble ore in Example 1 and red copper plate in Example 2) are verified by the original non-ignition performance test method (friction method), and the materials do not produce instantaneous spark. The method provided by the present application can provide reliable data, accurately evaluate the non-ignition performance of the material, and meet the actual needs.

[0069] Comparative Example 2

[0070] The two materials (cloud gray marble ore in example 1, white marble ore in example 3) are verified by the original non-ignition performance test method (friction method), and the cloud gray marble does not produce instantaneous spark, and the white marble has instantaneous spark. Comparison proves that not all marble raw materials can be used as aggregate for non-ignition materials. The method provided by the application can effectively screen the hard and easy-to-ignite raw materials in the marble aggregate, more accurately evaluate the non-ignition performance of the materials, meet the actual needs, and provide guidance for the selection of aggregate raw materials.

[0071] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for evaluating a non-firing material, characterized by, The method comprises the following steps: 1) treating the material to be tested to obtain a sample, the surface of the sample being flat and smooth; the material to be tested comprising particles, small-sized or irregular materials, and the material to be tested not containing iron products; 2) determining the Vickers hardness value of the sample; when the material to be tested is aggregate containing multiple mineral components, different parts, colors and crystal bodies are selected for hardness testing; the Vickers hardness value is calculated by using formula 1; HV = 0.1891 (F / d 2 ) Equation 1 wherein HV is the Vickers hardness value in N / mm 2 ; F is the test force in N; d is the two diagonal arithmetic average in mm; 3) comparing the Vickers hardness value of the sample with a threshold value to evaluate the non-ignition material of the material to be tested; when the Vickers hardness value of the material to be tested is less than 150, the material to be tested is determined to be a non-ignition material and can be used for non-ignition material and / or non-ignition material aggregate; when the Vickers hardness value of the material to be tested is greater than or equal to 150, the material to be tested is determined to be an easily ignitable material and cannot be used for non-ignition material and / or non-ignition material aggregate.

2. The method for evaluating non-ignition material according to claim 1, characterized by, In step 1), the material to be tested is polished to make the surface roughness of the test surface of the sample not greater than 0.8 μm.

3. The method for evaluating non-ignition material according to claim 1, characterized by, In step 2), the Vickers hardness value of the sample is determined at room temperature, and at least three test points are selected.

4. The method for evaluating non-ignition material according to claim 3, characterized by, In step 2), the Vickers hardness values of the test points are compared, and the maximum value is taken as the Vickers hardness value of the sample.

5. The method for evaluating non-priming material according to any one of claims 1 to 4, characterized in that, The method comprises the following steps: 1) sample preparation: selecting a material to be tested, polishing the material to be tested to obtain a sample; the test surface of the sample being flat, smooth and free of contamination, and the surface roughness being not greater than 0.8 μm; 2) Vickers hardness determination: determining the Vickers hardness value of the sample at room temperature, and randomly selecting at least three test points; for the material to be tested being aggregate containing multiple mineral components, different parts, colors and crystal bodies are selected as test points according to the sample condition, and the maximum value of the determined Vickers hardness value is taken as the Vickers hardness value of the material to be tested; calculating the Vickers hardness value by using formula 1; HV = 0.1891 (F / d 2 ) Equation 1 wherein HV is the Vickers hardness value in N / mm 2 ; F is the test force in N; d is the two diagonal arithmetic average in mm; 3) non-ignition material evaluation: comparing the Vickers hardness value of the sample with a threshold value to evaluate the non-ignition material of the material to be tested; when the Vickers hardness value of the material to be tested is less than 150, the material to be tested is determined to be a non-ignition material and can be used for non-ignition material and / or non-ignition material aggregate; when the Vickers hardness value of the material to be tested is greater than or equal to 150, the material to be tested is determined to be an easily ignitable material and cannot be used for non-ignition material and / or non-ignition material aggregate.

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