A dynamic test of metals is the sclero scope hardness test, where the height of rebound of a hammer is used as a measure of the hardness. Depending on the hardness scales of your choice, from any of shore scales a, a0, b, 0, c, d, d0, 00, 000, 000 s, e, micro shore a, micro shore d, c, d0. Abstract the objective of this experiment is to measure the hardness values of different specimens using four test methods. Durometer type a for materials such as e lastomers. Shore hardness gauge din 53505 iso 868 astm d2240 tqc. Chandrasekaran, in essential rubber formulary, 2007. Hardness conversion chart provides values for brinell. Shore durometer hardness testing of rubber and plastics matweb. Semirigid plastics can also be measured on the high end of the shore. There are different shore hardness scales for measuring the hardness of different materials. For example, both the hardness test and the tensile test measure the. The test methods employed vary greatly from a field applied test to a very controlled laboratory test. Standard test method for rubber propertydurometer hardness.
Durometer shore hardness test manual ld0550, ld0551. One of the most popular hardness testing methods, brinell hardness number is obtained using a perfectly spherical hardened steel ball of 10 mm pressed against the test surface using a static force of 3000 kg 29. Shore d hardness test durometer scale hardness of plastic. The measuring instrument is actually a durometer, but shore hardness is named after its inventor albert shore. Use of shore hardness tests for inprocess properties. Shore a vs shore d hardness 165 wambold road, harleysville, pa 19438 18005236688 2157236051 fax 2157992518 shore hardness astm d2240 shore hardness is a relative measure of exactly what the term implies hardness. Principally, the importance of hardness testing has to do with the relationship between hardness and other properties of material. Stiffness is measured objectively by a flexural modulus test. While there is perhaps a loose correlation, they are not the same.
The importance of shore a hardness gallagher fluid seals. D785 test method for rockwell hardness of plastics and electrical insulating materials. Higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. The ease with which the hardness test can be made has made it the most common method of inspection for metals and alloys. Shore hardness gauge din 53505 iso 868 astm d2240 tqc sheen. According to astm d224015 standard test method for rubber property durometer hardness, the test specimen must be at least 6.
The shore durometer is a device for measuring the hardness of a material, typically of polymers, elastomers, and rubbers. Shore a hardness scale cross references extra soft soft medium hard shore 00 shore a shore d shore 0 shore b shore c 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80. The geometry of the indentor and the applied force influence. Shore hardness test a and d ld0550, ld0551 product description the shore hardness gauge is a reliable instrument for measuring the impression hardness of soft materials such as coatings, plastics and rubber. Hardness comparison of polymer specimens produced with. Shore hardness is a measure of the resistance of a material to penetration of a spring loaded needlelike indenter. Hardness may be defined as a materials resistance to permanent.
Durometers with maximum reading indicators used to determine maximum hardness values of a material may yield lower hardness when the maximum indicator is used. Pdf influence of the indenter shape in rockwell hardness test. The shore hardness is a characteristic value that is used predominantly for elastomers, soft rubbers and very soft plastics. Shore hardness is sometimes confused with stiffness in the tpe world. The hardness is measured by the depth of indentation caused by a rigid ball under a spring load or dead load, the indentation being converted to hardness degrees on a scale ranging from 0 to 100. Influence of the indenter shape in rockwell hardness test.
Digitest ii automatic motorized hardness testing system. D1415 test method for rubber propertyinternational hardness. Click here to download a pdf of the shore hardness scale. The shore durometer is a device for measuring the hardness of a material, typically of polymers, elastomers, and rubbers higher numbers on the scale indicate a greater resistance to indentation and thus harder materials. Shore hardness is nothing but a measure of the hardness of a given material or how resistant it will be to permanent indentation. In the lab, we use the two most common rockwell scales. Durometer is one of several measures of the hardness of a material.
The test device ensures that the hardness tester is exactly perpendicular to the specimen surface, leading to a significant reduction overall in measuredvalue scatter during hardness tests and is recommended for laboratory tests, as testprocedure repeatability is considerably improved if. The indenter is forced into the test material under a preliminary minor load 0 fig. Shore d hardness is a standardized test consisting in measuring the depth of penetration of a specific indenter. This document specifies a method for determining the indentation hardness shore hardness of vulcanized or thermoplastic rubber using durometers with the following scales.
The reading from a dead load hardness meter is called international. For testing the hardness of the material, parker recommends shore a hardness. Hardness of polymers rubbers, plastics is usually measured by shore scales. The resulting indentation depth is a measure for the shore hardness. The principal purpose of the hardness test is to determine the suitability of a material for a given application, or the. The device consists of a hardened steel rod with a truncated cone at the tip. It is possible to pile several specimens to achieve the 6. It is directly related to the indentation depth and serves as a mea sure of the material hardness. Shore a and d, delivery includes a simple test block. The hardness value is determined by the penetration of the durometer indenter foot into the sample. The shore durometer is a device for measuring the hardness of a material, typically of polymers. Hrc rockwell c scale hardness hv vickers hardness brinell hardness hb 10 mm ball load 3000 kgf. Testing rubber, plastic, leather and all other soft materials. Shore a hardness scale cross references extra soft soft medium hard shore 00 shore a shore d shore 0 shore b shore c 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 6 7 8 10 12 14 16 19 22 25 29 33 39 46 60 75 90 8 14 21 28 35 42 48 53 57 61 65 69 72 75 79 84.
The indentation hardness is inversely related to the penetration and is dependent on the elastic modulus and viscoelastic behavior of the material. For minerals, a scratch test in which a harder mineral scratches into a softer one. Shore hsc, hsd scleroscope hardness shore hfrsc shore hs hschsd leeb hld hle astm e 140 astm a 427 jis b 7731 eqoutip proceq 940 68 97,3 98 890 855 926 67,6 96,8 105 97,2 886 850. Lower numbers indicate less resistance and softer materials. It is measured by the depth of indentation that is created on the material with a specified force. Pdf polymer hardness test analysis ian widi perdana. A reliable instrument for measuring the impression hardness of soft materials such as coatings. Hardness lab report hardness testing experiment 4 engr229. The most widely used hardness measuring instrument is called the durometer. Both methods measure the resistance of plastics toward indentation and provide an empirical hardness value that doesnt correlate well to other properties or fundamental characteristics. In general, hardness results can be converted from one scale to another, so long. Hardness testing and specimen preparation application notes.
Rubber elastomers are measured using the shore typea scale. Shore durometer hardness testing of plastics arcor epoxy. Shore a and shore d hardness scales are common, with the a scale being used for softer and the d scale being used for harder materials. Hardness conversion table primerjalna tabela trdot edatum. Apr 19, 20 shore a vs shore d hardness 165 wambold road, harleysville, pa 19438 18005236688 2157236051 fax 2157992518 shore hardness astm d2240 shore hardness is a relative measure of exactly what the term implies hardness. Feb 15, 2012 used to measure the hardness of rubber and plastics according astm d2240, din 53505, iso 868 and iso 7619. Using hardness scales with tpes star thermoplastics.
D618 practice for conditioning plastics for testing. This means the shore durometer hardness test is compatible with all selected materials and applicable. The higher the shore value is, the higher the dynamic restiffening tends to be. Shore hardness a is used for soft rubbers and shore hardness d for elastomers and very soft plastics. Shore a scale is used for testing soft elastomers rubbers and other soft polymers. This means the shore durometer hardness test is compatible with all selected materials and applicable manufacturing processes were selected for making these thermoplastic specimens. Shore a scale is applicable for rubber and soft plastics whereas shore d is for hard. A shore hardness test confirms our less objective determination and, more importantly, allows designers to specify a hardness number on their part specification thereby ensuring product quality and consistency from one part to the next. It is an industry standard test for rubber, and it is.
Any testing carried out as well as their results are dependent. Rockwell hardness test the rockwell hardness test is a hardness measurement based on the net increase in depth of impression as a load is applied. The term is also used to describe a materials rating on the. The shore 00 hardness scale measures rubbers and gels that are very soft.
This shows the limitation in simply modifying bushes for a higher load case by increasing the shore hardness of the rubber compound. D49 practice for rubberstandard conditions for testing. Standard test method for rubber propertydurometer hardness1. The test device ensures that the hardness tester is exactly perpendicular to the specimen surface, leading to a significant reduction overall in measuredvalue scatter during hardness tests and is recommended for laboratory tests, as test procedure repeatability is considerably improved if operator influence is eliminated. It measures hardness values in pointsthat range from 0 to 100. The failure modes are associated with the stress distribution, which are a direct result of the scratch test variables, such as hardness of materials, applied load, scratch distance, geometry of. The shore a hardness scale measures the hardness of flexible mold rubbers that range in hardness from very soft and flexible, to medium and somewhat flexible, to hard with almost no flexibility at all. Shore durometer hardness testing of plastics the hardness testing of plastics is most commonly measured by the shore durometer test or rockwell hardness test. Stiffness is a great test for something such as tubing applications where the tube may have to bend around a radius or resist kinking. Shore durometer hardness test microcoat technologies. The most widely used device is a shore hardness meter. Sep 20, 2016 the shore a hardness measurement is often colloquially called durometer or duro. The shore hardness cannot replace the correct establishment of the static and dynamic stiffness of the component. Hardness conversion chart provides values for brinell, rockwell a, rockwell b, rockwell c, rockwell d, rockwell e, rockwell f, rockwell superficial 15n, rockwell superficial 30n, rockwell superficial 45n, rockwell superficial 30t, vickers 6, shore, and tensile strength psi hardness.
Jis z 2244 approximate conversion values for rockwell c hardness values of steel 1 technical data conversion table of hardness sae j 417 revised 1983. The tqc shore hardness gauge is a reliable instrument for measuring the impression hardness of soft materials such as coatings, plastics and rubber. Hardness of hard elastomers and most other polymer materials thermoplastics. The hardness testing of plastics is most commonly measured by the shore. Test methods used to measure shore d hardness are astm d2240 and iso 868. Equipped with a drag indicator, which holds the highest measured result. Durometer shore hardness test ld0550, ld0551 application a reliable instrument for measuring the impression hardness of soft materials such as coatings, plastics and rubber. Introduction to hardness testing asm international. Shore durometer hardness testing of plastics is described, and conversion charts correlating various scales are presented. Durometer shore hardness is used to test silicone rubbers as a model material with different compositions on different moulding planes and the linear elastic. The shore a hardness measurement is often colloquially called durometer or duro. According to the standard din 53505 valid until 2012, a distinction is made between the hardness methods shore a and d. In general, hardness results can be converted from one scale to another, so long as the test is examining the same type of hardness. Object the hardness test is a mechanical test for material properties which are used in engineering design, analysis of structures, and materials development.
667 857 141 1647 1260 753 255 443 1427 137 125 505 1033 620 447 1249 1239 1071 820 723 1355 1280 1286 1366 1528 223 832 692 561 372 351 110 1227 927 922