ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
1. 개요
1.1 이 시험 방법에는 가황 열경화성 고무 및 열가소성 엘라스토머의 인장 특성을 평가하는 방법이 포함됩니다.. 이 시험 방법은 단단한 접착제와 경도가 높고 신율이 낮은 재료를 시험하는 데 사용할 수 없습니다.. 시험방법은 다음과 같다:
방법 A — Straight bar and dumbbell samples
방법 b — 환형 시편
주목 1 -the results of the two tests are incomparable.
1.2 SI 또는 비 SI를 기반으로 한 단위는이 표준의 표준 단위로 간주됩니다.. Since the results of using different unit systems may be different, 다른 단위는 별도로 사용하고 혼합되지 않아야합니다..
보안
2 참조
디 1349 고무 사양 — Standard test temperature
디 1566 Rubber related terminology
디 3182 고무 사양 — 재료, equipment and procedures for making standard compounds and standard vulcanization test pieces
디 3183 고무 사양 — Preparation of test pieces from finished products
디 4483 Standard test methods for rubber and carbon black industrial species – Specification for measurement accuracy
2.2 ASTM Annex
환형 시편의 준비, 방법 b
ISO 표준
ISO 37 – Methods for determination of tensile stress-strain properties of vulcanized or thermoplastic rubber
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
3 술어
3.1 Definitions
3.1.1 인장 장기 변형 — The residual deformation of the sample after elongation under a certain action, when the applied force is relieved, 원래 길이의 백분율로 표현됩니다.
3.1.2 Long stretching deformation — The long stretching deformation of the pulled dumbbell sample is closely pressed to the cross section.
3.1.3 인장력 — The maximum force generated in the process of breaking the sample.
3.1.4 인장 강도 — the stress used when drawing the sample
3.1.5 일정한 연장 응력 — the stress generated when a sample of regular section is stretched to a specific length.
3.1.6 Thermoplastic elasters — a material similar to rubber, 그러나 평범한 가황 고무와 달리, 플라스틱처럼 가공 및 재활용 할 수 있습니다.
3.1.7 휴식시 신장 — the elongation of the specimen when it breaks during continuous stretching.
3.1.8 항복점 — The point on the stress-strain curve where the velocity of the stress change with respect to strain becomes 0 and opposite before the final failure of the specimen.
3.1.9 수율 변형 — 항복점에서의 변형 수준
3.1.10 항복 스트레스 — 항복점에서의 응력 수준
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
Method Description
4.1 For the test of tensile properties, samples are first cut from the sample material, including two parts: sample preparation and test. The shape of the specimen can be dumbbell, 반지 또는 직선 막대, 그리고 섹션 모양은 규칙적입니다.
4.2 Determination of tensile strength, 고정 스트레스, 샘플의 사전 확장없이 휴식시 항복점 및 신장. 인장 강도의 결정, 고정 스트레스, yield point and elongation at break for the specimen with normal section is based on the original cross-sectional area of the specimen.
4.3 Long-term deformation by stretching and long-term deformation by tearing, measure the deformation of the sample after stretching and shrinking according to the prescribed method.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
Key Points and Applications
5.1 이 테스트와 관련된 재료 또는 제품은 실제 적용 과정에서 인장력을 적용해야합니다.. This test is to determine such tensile properties. 하지만, the tensile properties do not directly represent the whole situation of the final use of the product, because the product needs to cover a wide range of potential use conditions in actual use.
5.2 Tensile properties are dependent on materials and test conditions (인장 속도, 시험 온도 및 습도, 샘플 형상, 사전 테스트 조정, 등.). 그러므로, 동일한 조건에서 재료의 테스트 결과는 비슷합니다..
5.3 Test temperature and tensile speed have significant effects on tensile properties, 엄격하게 제어해야합니다. And the effect varies with different materials.
5.4 인장 장기 변형은 샘플의 잔류 변형을 나타냅니다.. 스트레칭 및 후퇴 후 샘플의 장기 변형 및 부분 복구를 나타냅니다.. 그러므로, 스트레칭 및 철회 프로세스 (그리고 다른 테스트 조건) need to be tightly controlled to ensure comparable results.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
6 장비
6.1 인장 기계 — The tensile testing machine shall have an electric drive mechanism to ensure that the separation speed of the sample chuck is constant 500±50mm/min, and the minimum stroke is 750mm(참고를 참조하십시오 1). The testing machine should have a suitable dynamometer and reading recording system to ensure that the measured force deviation is within ±2%. 테스트 기계의 범위를 변경할 수없는 경우 (예를 들어, 진자 동력계), then the deviation of the measured force when the sample is broken is ±2% of the full range of the dynamometer, and the accuracy of the measured minimum force is 10%. If the dynamometer has an automatic compensation function in the direct measurement of tensile stress, then the compensation function for the cross-sectional area of the specimen should be turned off during the measurement. The recording device should be fast enough to measure the force and ensure the required accuracy during the whole process of specimen failure. If the testing machine does not have a recording device, there should be an indicator to indicate the maximum force value during stretching. 신장은 최소 증분으로 테스트 시스템에서 측정해야합니다. 10%.
메모 1 — 사용 된 인장 속도가 1000 ± 100mm/분인 경우, 테스트 보고서에 표시되어야합니다. In case of doubt, the test should be repeated at a speed of 500mm/min.
6.2 High and low temperature test box — the test box should meet the following requirements:
6.2.1 테스트 챔버에서, there should be a heat flow around the position of the chuck and the shaft, 서라운드 속도는입니다 1 2m/s까지, and the temperature is kept within the range of 2 ° C of the required temperature deviation.
6.2.2 Use the calibrated temperature measuring device to measure the actual temperature near the chuck and shaft.
6.2.3 The test chamber shall have an exhaust ventilation device to discharge the gas released in high temperature (견본) into the atmosphere.
6.2.4 시험 전, 샘플은 척과 샤프트 근처에 수직으로 배치되어야합니다.. Specimens should not be in contact with each other or with the walls of the test chamber except for transient contact caused by agitation of the surrounding air.
6.2.5 Place the chuck appropriately to facilitate operation in high and low temperature environments. 이런 식으로, the dumbbell or straight strip specimens are placed into the chuck for as short a time as possible to reduce the temperature change of the test chamber.
6.2.6 The dynamometer should be suitable for working at the test temperature, or have good insulation with the test chamber.
6.2.7 Elongation measuring device shall be provided in the test chamber. If a ruler is used to measure the elongation of the specimen scale, the ruler should be placed parallel to the scale close to the path of the chuck movement and can be controlled from outside the test chamber.
6.3 Thickness gauges — Thickness gauges shall meet the requirements of Specification D 3767(방법 A). 환형 표본의 경우, 기사를 참조하십시오 14.10 이 테스트 방법의.
6.4 인장 장기 변형 측정 — Use test equipment as described in 6.1 또는 그림과 같이 1. The stopwatch or other timing device should have a range greater than 30min, and the measuring accuracy of the ruler or other measuring device for elongation should be within 1%.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
7 샘플 선택
7.1 The following points should be considered when selecting samples
7.1.1 The anisotropy and orientation of the material caused by the flow during preparation and treatment can affect the tensile properties. 그러므로, in the preparation of dumbbell or straight bar specimens, under the premise of knowing the calendering direction, 샘플 절단 방향은 캘린더 방향과 평행해야합니다.. 환형 표본의 경우, the orientation characteristics are usually averaged to a certain extent.
7.1.2 달리 명시되지 않는 한, for thermoplastic rubbers or elasteers, specimens shall be cut from injection molded specimens with a thickness of 3.0±0.3mm, and the test results obtained from specimens of other thicknesses shall be comparable. The samples should be two sets of perpendicular and parallel forming flow directions. The size of the test piece or test plate should be able to meet the test requirements.
7.1.3 The elongation of the annular specimen can be measured by the separation of the collet, but the elongation distribution on the radius width of the specimen is inconsistent. 이 효과를 줄입니다, the sample width should be smaller than the diameter of the annular sample.
7.1.4 When the sample is used for ordinary tensile test, the failure of the sample generally occurs in the chuck. 그러므로, the straight bar specimen is used only when the sample cannot be made of other shapes. For non-destructive stress-strain or material modulus experiments, straight strip specimens should be used.
7.1.4 샘플의 크기는 재료의 요구 사항에 따라 다릅니다., 테스트 장비와 테스트에 사용 된 샘플. 휴식시 신장이 낮은 재료의 경우, longer specimens can be used to improve the accuracy of elongation measurement.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
테스트 장비의 교정
8.1 Calibrate the test machine according to Procedure A of Specification E 4 for dynamometers of measuring precision type, and calibrate one or more force points according to the 7 그리고 18 test of specification E 4. For pendulum dynamometers, 다음 단계를 따라 교정하십시오:
8.1.1 아령 샘플의 한쪽 끝을 테스트 머신의 척에 넣으십시오..
8.1.2 테스트 머신에서 하단 척을 제거하십시오, 즉,, the clamping mechanism of the sample is on the upper chuck of the testing machine.
8.1.3 하단 척에 고리를 설치하여 샘플의 아래쪽 끝을 잡습니다.
8.1.4 Hang a weight with a known weight on the hook, so that a certain mass can be temporarily applied to the lower fixture of the sample (참고를 참조하십시오 2).
8.1.5 Turn on the fixture movement monitoring device and keep it running until the weight is free to hang on the sample in the ordinary test.
8.1.6 If a disc or ruler (or equivalent tester for stress compensation) does not indicate force values within the specified accuracy, the equipment should be effectively checked for faults (예를 들어. friction on shafts or other moving parts). 하부 척과 후크의 질량도 고려한 것으로 결정해야합니다..
8.1.7 마찰 후 테스트 머신의 마찰 및 기타 결함이 제거됩니다., the testing machine is calibrated to know that the weight is measured at three points at about 10, 20 그리고 50% 테스트 기계의 전체 스케일. If ratchets and spines are used in normal testing, they should also be used in calibration. Friction is checked by mounting a ratchet.
메모 3 — There should be a device to prevent weights from falling from the test machine.
8.2 스프링은 대략적인 빠른 교정에 사용될 수 있습니다.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
9 시험 온도
9.1 달리 명시되지 않는 한, 표준 테스트 온도는 23 ± 2 °입니다. 샘플을 조정해야합니다 23 적어도 ° C 3 시간. 재료가 습도의 영향을받는 경우, 시편은 50 ± 5%R.H로 조절해야합니다. 이상 24 테스트 시간 전. 다른 온도에서 테스트 한 경우, 사양에 나열된 온도 d 1349 사용되어야한다.
9.2 If the test is carried out at A temperature higher than 23℃, 방법 A의 샘플은 10 ± 2 분 동안 예열해야합니다.; Method B should be preheated for 6±2min. 각 테스트 간격 전에, the specimens are placed in the test chamber separately, so that all specimens are continuously subjected to the same warm-up time. Preheating tests at high temperatures should be strictly limited to prevent persulphation and thermal aging.
메모 3 — 경고: 다른 경고 중, use insulated, cold gloves to protect hands from high and low temperatures. 실험 상자의 문이 열릴 때 독성 가스의 흡입을 방지하기 위해 고온 실험 중에 마스크를 사용해야합니다..
9.3 저온 테스트의 경우, 샘플은 최소 10 분 동안 사전 냉각되어야합니다.
테스트 방법 a — Straight bar and dumbbell specimens
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
10 장비
10.1 Cutting Knife — The shape and dimensions of the cutting knife shall be as shown in Figure 2. The inside of the narrow part of the cutter shall be perpendicular to the cutter end face and at least 5mm from the cutter end face shall be polished. The shape of the cutter should remain unchanged without defects. (참고를 참조하십시오 4)
메모 4 — 절단 도구의 상태는 샘플의 골절 점을 관찰하여 결정할 수 있습니다.. The fractured sample was removed from the chuck and spliced along the fracture surface to observe whether the sample failure occurred at the same location. 실패가 같은 위치에서 발생하는 경우, it means that the cutter may become blunt, 결함 있는, 또는이 위치에서 구부러졌습니다.
10.2 Marking lines — Two marking lines drawn on the sample to measure elongation and strain are called marking lines (참고를 참조하십시오 5). The marker shall include a flat plate with two bumps parallel to each other. 상승 된 표면 (플레이트 표면과 평행합니다) 길고 좁은 비행기가 있어야합니다, 그리고 두 얼굴은 같은 비행기에 보관해야합니다.. 제기 비행기는입니다 0.05 너비 0.08mm, 길이는 15mm 이상입니다. The Angle between the plate and the bulge was at least 75º. 두 개의 자란 비행기의 중심 사이의 거리는 안에 보관해야합니다. 1% of the required or target distance deviation. A handle shall be included on the back or top of the marker.
메모 4 — No marking is required if contact extensionometers are used.
10.3 Ink Marks — 아파트를 사용하십시오, 단단한 표면 (견목, 금속, 또는 플라스틱) to make ink or toner marks. The ink or toner should be firmly bonded to the sample, not corroding the sample, and contrast with the color of the sample.
10.4 Chuck — 테스트 미터에는 두 개의 콜렛이 있습니다, 그 중 하나는 동력계에 연결되어 있습니다.
10.4.1 The chuck of the test dumbbell sample should have a self-tightening device to generate constant pressure on the surface of the chuck, and the clamping force should increase with the increase of elongation to prevent sliding and make the failure occur in the narrow part of the sample. A constant pneumatic chuck is also applicable. There is a special part in the broken part of the fixture so that the sample can be inserted into the fixture with the same length and the stress distribution is uniform.
10.4.2 The fixture used for testing straight strip samples shall have pneumatic fixture, 입 또는 볼트 버클을 클램프하십시오, so that the clamping force of the fixture can be applied evenly to the entire width of the sample.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
11 견본
11.1 아령 표본 — 가능할 때마다, specimens should be injection molded or cut from specimens 1.3 두께 3.3mm. The thickness and size of the specimen can be cut by one test method (see Specification D 3182). 테스트 조각은 완제품에서 직접 만들거나 자르고 연마 할 수 있습니다.. If the test piece is prepared directly from the finished product, 표면은 단단한 가죽이나 직물이되어서는 안됩니다. According to the requirements of specification D 3183. All specimens shall be cut parallel to the length of the specimen, 달리 명시되지 않는 한. 사양에 따라 시편이 준비된 경우 d 3182, 두께는 2.0 ± 0.2mm이고 재료의 방향을 따라 절단해야합니다.. Use C type cutter (무화과. 2), use a simple stamping device, and ensure the smoothness of the cut surface. .
11.1.1 라벨링 아령 표본 — Dumbbell specimens shall be marked as described in 10.2, and the specimens shall not be subjected to tension when marked. The marking line should be drawn on the narrow part, at the same distance from the center of the sample and perpendicular to the vertical axis. The distance between the two marks is 25.00±0.25mm for type C and type D samples. The other is 50.00±0.5mm
11.1.2 dumbbell sample thickness measurement — The thickness of the sample should be measured at three points, one at the center and two at the ends of the narrow part. The median of the three values is used to calculate the cross-sectional area. 샘플 두께의 범위가 0.08, the sample is rejected. 샘플의 너비는 커터의 작동 부분의 폭에 따라 계산할 수 있습니다..
11.2 스트레이트 스트립 시편 — If dumbbells or annular specimens cannot be cut from the sample, 스트레이트 스트립 시편 (e.g., narrow strips, 작은 튜브, or fine electrical insulation) can be cut. 시편은 고정물에 맞을 정도로 길어야합니다.. The marking is made as 11.1.1. 튜브에서 테스트 단면 영역을 계산합니다, 질량, 튜브의 길이와 밀도를 사용해야합니다. 단면 영역은 다음과 같이 계산됩니다:
A=M/DL(1)(1)
어디:
a = 단면적,cm2
m = 질량,g
d = 밀도,G / CM3
l = 길이,센티미터
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
12 단계
12.1 인장 스트레스 결정, 인장 강도 및 항복점 — 아령 샘플을 테스트 머신의 고정물에로드하십시오., pay attention to adjust the gripping symmetry of the sample, 인장력이 샘플 섹션에 골고루 분포되도록. 이것은 시편의 인장력의 과대 평가를 피할 것입니다.. The test speed is 500±50mm/min(참고를 참조하십시오 7) unless special requirements are required. Start the testing machine and pay attention to the marking to prevent the influence of parallax. The force values at special elongation and at fracture of the sample were recorded. Elongation can be measured using extensionmeters, automated plotting, or optical tracking systems. 골절에서의 신장 측정 정확도는 내부에 있습니다 10%. The calculation is given in 13.
메모 8 — 샘플의 항복점이 아래에있는 경우 20% 시험 속도가 500 ± 50mm/분인 경우, 시험 속도는 50 ± 5mm/분로 감소 될 수있다. 샘플의 항복점이 여전히 아래에있는 경우 20% 연장, the test speed can be reduced to 5±0.5mm/min. Sample speed should be recorded.
12.2 Determination of tensile long-term deformation — The sample is loaded into the testing machine or device described in 6.1 as shown in Figure 1. Care should be taken to adjust the gripping symmetry of the sample so that the tensile force is evenly distributed on the sample cross section. The speed of the chuck separation should be as constant as possible, so that the time to reach the prescribed elongation is 15s, and this elongation is maintained for 10min. After 10min, the load was released immediately and allowed to return freely for 10min. After that, the residual deformation within the standard distance was measured, and the measurement accuracy was 1% of the original distance. Use a stopwatch to track the time. 보다 13 계산을 위해.
12.3 Measurement of long-term fracture deformation — 샘플이 10 분 동안 파손 된 후, the sample should be carefully spliced together to measure the residual deformation within the standard distance, and the calculation is shown in 13
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
13 계산
13.1 모든 신장시 강도 계산:
where
티(트리플 엑스)= 신장시 강도 (트리플 엑스)%,MPa
에프(트리플 엑스)= 특정 신장시 스트레스,MN
A= cross-sectional area of the sample,M2
13.2 항복 강도의 계산
where
와이(스트레스)= 항복 강도,MPa
에프(와이)= 수율 힘,MN
A= cross-sectional area of the sample,M2
13.3 The yield point is evaluated as the point on the stress-strain curve where the velocity of the stress change with respect to strain becomes zero and opposite before the final failure of the specimen.
13.4 인장 강도의 계산
where
TS = 인장 강도,MPa
에프(BE)= maximum force at fracture,MN
A= cross-sectional area of the sample,M2
13.5 Compute the elongation at any elongation;
where
e = 백분율 신장 (규모의 거리),%
L = 샘플 표준 거리 내에서 관찰 된 거리,mm
엘(0)= length of the sample’s original marking distance,mm
13.6 Elongation at break is calculated by substituting L at the time of sample fracture into Equation 5.
13.7 공식 5 can also be used to calculate long-term deformation, as long as L in the formula is substituted by the residual deformation after 10 분.
13.8 Test Results — 테스트 결과는 3 개의 독립적 인 연속 샘플의 결과의 중앙값으로 표현됩니다.. 두 가지 특별한 경우, 5 개의 샘플을 테스트하고 5 개의 샘플의 중앙값을보고했습니다..
13.8.1.특별한 경우 1 — When the results of one or two samples in the test do not meet the specified measurement.
13.8.2 특별한 경우 2 — For arbitral tests.
방법 b — 환형 시편
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
14 장비
14.1 커터 — A circular cutter is shown in Figure 3. Use a cutting knife to cut the annular sample from the flat test piece, and install a part of the upper shaft of the cutting knife into the rotary compression device, under which the test piece can be fixed in the rubber fixing device.
14.1.1 블레이드 깊이 리테이너 — The cylindrical disk in the retainer shall be at least 0.5mm thicker than the thickness of the rubber sheet to be cut. Its diameter should be smaller than the inner diameter of the sample, 블레이드의 돌출부를 절단 도구에서 조정할 수 있도록. 그림을 참조하십시오 3
14.2 고무 고정판 — A device for holding rubber in place during cutting, the upper and lower surfaces parallel to each other, and made of hard polymeric materials (단단한 접착제, 폴리 우레탄 및 폴리 메틸 메타 크릴 레이트). Holes of about 1.5mm in diameter are distributed at intervals of 6 to 7mm through the center of the plate. All these holes shall communicate with the mold cavity inside to reduce the air pressure used to hold the test piece. 수치 4 is used to hold the standard test piece (약 150 × 150 × 2mm) 절단 중.
14.3 공기 압력 공급원 — A vacuum pump can be used to maintain a suction force of 10kPa on the specimen at the center of the gripper mold cavity.
14.4 Soapy water — Use neutral soapy water to lubricate the knife.
14.5 로타리 절단 — Use a precision rotary machine or other equipment that can provide a speed of at least 30rad/s to cut the test piece. The cutter rotating device shall be mounted on a horizontal plane with a vertical positioner to support the rotating connecting rod and the shaft used for the cutter. 회전 샤프트의 편심은 0.01mm 미만이어야합니다..
14.6 Built-in table — There shall be a table or other device that can be moved along the x-y axis respectively to hold and position the test piece so that the test piece corresponds to the axis of rotation of the rotary cutter.
14.7 Tensile testing machine — shall comply with the requirements described in 6.1.
14.8 테스트 고정물 — The fixture of the annular sample is shown in Figure 5. 테스트 머신에 따라 교정해야합니다 8 articles.
14.9 Test chambers — High and low temperature test chambers shall meet the requirements in 6.2.
14.9.1 고정물은 실온에서 테스트에 적합하지 않아야합니다.. 하지만, 특수 온도에서, 회전 샤프트의 윤활을 보장하기 위해 적절한 윤활을 사용해야합니다..
14.9.2 동력계는 작동 온도에서 사용하거나 테스트 챔버에서 잘 절연해야합니다..
14.10 두께 게이지 — Thickness gauges shall meet the requirements of Specification D 3767(방법 A).
14.10.1 The main components of the thickness gauge, 원통형 상부 측정 표면 (longitudinal axis along the vertical direction) 지름이 최소 12mm 및 15.5 ± 0.5mm. In order to fit the small annular sample, the measuring head with diameter of 15.5mm is used to measure, 그리고 측정은 샘플의 신장을 유발하지 않습니다.. The bottom of the cylindrical surface can be cut off half along the center so that there is no interference when measuring small samples. 곡선 측정 끝도 사용할 수 있습니다.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
15. 환형 시편
15.1 ASTM 환형 시편 — 두 가지 유형이 있습니다, generally 1-shaped specimens are used
15.1.1 표본의 크기
유형 1
The inner perimeter is 50.0±0.01mm
내 직경은 15.92 ± 0.003mm였다
The radial width is 1.0±0.01mm
The thickness is 1.0~3.3mm
유형 2
The inner perimeter is 100.0±0.2mm
내 직경은 29.8 ± 0.06mm였다
The radial width is 2.0±0.02mm
The thickness is 1.0~3.3mm
15.2 ISO 환형 시편 — Specimens are classified as normal and small according to ISO 37, 특정 테스트 절차를 지정합니다.
평범한
The inner diameter is 44.6±0.2mm
The outer diameter is 52.6±0.2mm
The thickness is 4.0±0.2mm
작은 크기
내 직경 8.0 ± 0.1mm
외경 10.0 ± 0.1mm
The thickness is 1.0±0.1mm
15.3 파이프에서 환형 샘플을 자릅니다 — the diameter of the annular sample should be determined by the wall thickness of the pipe and should meet the requirements of the product.
15.4 절단 샘플의 준비 — Place the blade in the holder of the cutter and adjust the depth of the blade. 절단기를 로터리 프레스에 놓고 샤프트 홀더의 바닥이 샘플 고정 플레이트 위로 13mm가되도록 샤프트 또는 테이블을 조정하십시오.. Shrink the stopper with the rotating shaft moving vertically. This allows the end of the blade retainer to penetrate the surface of the plate. The sample was placed into the gripper and the cavity pressure was reduced to 10kPa. 중성 비눗물로 테스트 조각의 표면을 적시십시오.. The cutter should be stopped after reducing the cutter at a constant speed, and the cutter gripper should not touch the test piece at this time. Adjust blade depth if necessary. Reset the shaft before the next cutting.
15.5 Preparation of a sample cut from a tube — A shaft is inserted into the tube, the diameter of which is slightly larger than the diameter of the tube. Place the shaft and tube together on the machine tool. The specimen of the required axial thickness is cut from the sample with the blade or cutter on the machine tool. For thin-walled tubes, when laid flat, a cutter with two parallel blades can be used to cut.
15.6 Annular sample:
15.6.1 Perimeter — The inner perimeter can be measured with a cone or gauge. 측정 중에 환형 시편의 타원을 변화시키는 데 응력이 사용될 수 없습니다.. 중간 주변은 내부 주변을 기반으로 할 수 있습니다., meridional width, and π(3.14).
15.6.2 방사형 폭 — Distribute three measuring points equally on the circumference of the specimen as per the thickness gauge in 14.10.
15.6.3 두께 — The thickness of the disk from the inner circle to the outer circle can be measured by a thickness meter according to specification D 3767 when cutting annular specimens.
15.6.4 Cross-sectional Area — Cross-sectional area was calculated as the median of three measurements: radial width and thickness. For thin pipe wall samples, the cross-sectional area was calculated using the axial length of the cutter and the wall thickness.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
16 Process
16.1 인장 스트레스 결정, 인장 강도, elongation at break and yield point of annular specimens – with suitable lubrication of shafts with lubricating fixture, such as mineral oil or silicone oil. Should choose to use the prescribed and have no impact on the material. The calculation and adjustment of the initial position of the shaft center of the two fixtures are as follows:
어디:
IS= initial distance from the center of the jig axis,mm
씨(TS)= perimeter of the sample, 유형 1 샘플은 내 직경입니다, 유형 2 샘플은 직경입니다,mm
씨(sp)= circumference of the jig shaft,mm
The test speed was 500±50 mamms (메모를 참조하십시오 7 그리고 8), unless otherwise required. Start the test machine and record the force and the relative displacement of the two jig axes. Elongation and stress were recorded at fracture. The calculations are given in Section 17,
메모 8 — The test speed was 100±10mm/min using small ring type samples of ISO.
16.2 비표준 온도에서의 실험 — 설명 된대로 테스트 챔버를 사용하십시오 6.2 and read the warning in Note 2. For tests higher than 23 ℃, 이 온도에서 6 ± 2 분 동안 샘플을 예열시켰다. 실온 미만의 테스트, 샘플은 그 온도에서 최소 10 분 동안 조정해야합니다.. d.의 시험 온도 1349 사용해야합니다. Test pieces shall be placed in test chambers separately to meet requirement 9.2.
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
17 계산
17.1 하나의 중요한 요점을 제외하고, the stress-strain properties of the ring specimen are calculated as those of the dumbbell or straight strip specimen. 환형 시편이 뻗어있을 때, the stress distribution of each edge of the annular specimen is not uniform in width (왼쪽에서 오른쪽으로). The initial inner diameter of the sample is smaller than the initial outer diameter. 그러므로, the stress in the inner test is greater than that in the outer test in the sample stretching, caused by the different initial size.
17.2 The following options are available for calculating tensile and breaking strengths.
17.2.1 Fixed elongation stress — The median perimeter of the annular specimen was used to calculate the elongation. The reason for using the median perimeter is that it corresponds to the average over the edges of the annular specimen.
17.2.2 휴식시 신장 — 환형 시편의 내부 둘레는 계산의 기초로 사용됩니다., as it corresponds to the maximum stress on each edge of the specimen. This position is also the starting position of the sample failure.
17.3 일정한 연장 응력은 방정식에 따라 계산됩니다 2 ~에 13.1
17.3.1 신장은 방정식의 힘을 결정하는 데 사용됩니다 2 (13.1) 다음과 같이 계산됩니다
어디:
e = 신장,%
L= increase in the distance between fixtures,mm
MC(TS)= 샘플의 중간 주변,mm
17.3.2 In Equation 7, the distance between fixtures at fixed extension is calculated using the following equation:
17.4 항복점은 방정식에 따라 계산됩니다 3 ~에 13.2
17.5 사용 13.3 to determine the yield stress. 항복 응력은 재료의 전체 특성을 평가하는 데 사용되므로, 중간 주변은 계산하는 데 사용됩니다.
17.6 Calculate tensile strength according to Formula 4 ~에 13.4.
17.7 Elongation at break is calculated according to the following formula (메모를 참조하십시오 9 그리고 10)
어디:
e = 휴식시 신장,%
L= the increased distance of the fixture at break,mm
IC(TS)= 패턴의 초기 내부 둘레,mm
17.8 The inner perimeter can be used for both types of specimens (보다 15.1.1 치수). 유형의 내부 둘레 2 환형 시편은 내 직경을 사용하여 계산됩니다.
메모 9 — 방정식 7 그리고 8 can only be used if the initial spacing of the fixture is adjusted according to Equation 7.
메모 10 — Caution should be taken when using this method because stresses at elongations slightly below the elongation at break (4 에게 5%) may not be calculated when different sizes are used to calculate 1) fixed elongation stress (less than the breaking stress) 그리고 2) 휴식시 신장 (보다 20.1 그리고 20.2).
ASTM D412-0 “가황 고무 및 열가소성 엘라스토머의 인장 시험 방법”
18 Report
18.1 The report should include the following:
18.1.1 Based on the results of Section 13 또는 17
18.1.2 Sample type and description, according to the 13-section cutter type, in American, homemade or metric units
18.1.3 Date of experiment
18.1.4 테스트 속도
18.1.5 Laboratory temperature and humidity
18.1.6 시험 온도 (if not 23±2℃)
18.1.7 Date of vulcanization or (그리고) rubber preparation, if possible
19 Accuracy in deviation (omitted)
20 Key Words (omitted)