Spencer Impact Testing Method
ASTM D3420

の Spencer impact test is a standardized method used to determine the impact resistance of plastic films under dynamic loading conditions. By mimicking real-world puncture scenarios, this test offers insight into how a film will perform in packaging and industrial applications. Following ASTM D3420, this method allows professionals in quality control and product development to ensure material toughness and durability.

Understanding the Film Impact Resistance Test

の film impact resistance test measures the amount of energy required to puncture a plastic film sample using a pendulum impact tester. This dynamic method is more representative of actual use conditions than static tensile tests and is especially important for films used in packaging, medical device protection, and food sealing.

によると ASTM D3420, there are two procedures for the test:

Procedure A uses a 60 mm aperture and a larger impact head.
Procedure B、別名 Spencer impact test, uses an 89 mm aperture and is widely adopted for higher energy tests.

Importance of Spencer Impact Testing in Quality Control

Plastic films, though lightweight, are often used as the first line of defense in protecting goods. Whether sealing food, pharmaceuticals, or sensitive electronics, a rupture could compromise the entire product. The Spencer impact test simulates the impact stresses that these materials might endure in storage or transit. This is critical for:

Packaging manufacturers verifying the robustness of materials
Pharmaceutical companies ensuring sterility is maintained
Electronics firms protecting components from environmental stress

The test allows industries to quantify impact resistance in joules (J) または centimeter-kilogram-force (cm·kgf), providing consistent data for material comparison.

How to Conduct the Spencer Impact Test

To achieve consistent and reliable test results, follow the steps outlined in ASTM D3420 Procedure B:

Equipment Requirements

To perform the Spencer impact test, you need:

あ pendulum impact tester with a calibrated energy readout
An impact head with a 19.0 mm diameter and 12.7 mm radius
Clamps with an 89 mm aperture—preferably air-operated O-ring types to minimize slippage
Auxiliary weights for adjusting energy scales
Micrometer for precise thickness measurement
Circular or square test specimens, free from defects, generally 0.1–0.4 mm in thickness

サンプルの前処理とコンディショニング

Condition specimens per ASTM D618 at 23 ± 2°C そして 50 ± 10% RH before testing. Cut at least five specimens of consistent size and thickness. Use wax pencil marks near the clamp edge to detect slippage post-test.

テスト実行

Place and clamp the sample in the impact tester.
Zero the energy scale or digital readout.
Raise and release the pendulum to puncture the film.
Catch the pendulum on the return swing.
Record the energy reading (scale value).
Repeat for all specimens and calculate the average.

Note: If the pendulum does not puncture the film, increase the energy or use a thinner sample.

Energy Calculation

For Procedure B (Spencer method):

E = (R / 100) × C

どこ：

E = impact energy (J)
R = scale reading
C = capacity of apparatus (e.g., 0.17, 0.34, 0.67, 1.35, 2.7 J)

Reporting Requirements

Ensure your report includes:

Complete sample identification
Test procedure used (Spencer = Procedure B)
Pendulum energy capacity
Average impact strength and thickness
Environmental conditions
Standard deviation (if required)

Why Choose the PIT-01 Pendulum Impact Tester from セルインストゥルメンツ?

For reliable and repeatable Spencer impact test results, the Cell Instruments PIT-01 Pendulum Impact Tester is an ideal solution. Designed specifically to meet ASTM D3420 standards, PIT-01 offers:

Modular pendulum heads for both Procedure A and B
Digital readouts for precise energy readings
Air-operated clamping systems to eliminate slippage
Multiple energy scale support, including auxiliary weights

PIT-01 is widely adopted in R&D labs, QC departments, and production lines for film impact resistance tests. It ensures accurate, efficient, and reproducible results across a wide range of film materials.

さまざまな業界への応用

の Spencer impact test is suitable for industries including:

Food packaging: Testing multilayer films, vacuum pouches
Medical and pharmaceutical: Ensuring sterility through tough barrier films
エレクトロニクス: Evaluating protective wraps and anti-static films
Industrial packaging: Heavy-duty sacks and liners

Each application benefits from the detailed energy data provided, helping optimize material selection and quality assurance.

結論

の Spencer impact test, performed according to ASTM D3420, is a cornerstone method for evaluating the durability and toughness of plastic films in real-world scenarios. By using equipment like the PIT-01 Pendulum Impact Tester from Cell Instruments, manufacturers can ensure their materials meet industry standards and application demands.

Whether you’re in packaging, medical, or electronics industries, mastering the film impact resistance test ensures performance, safety, and quality.

Spencer Impact Testing Method ASTM D3420