Detailed explanation of Hengsi Cantilever beam impact test machine

Impact testing machineThere are many types of instruments and equipment with performance, which are divided into: cantilever beam impact testing machine, semi-automatic impact testing machine, fully automatic impact testing machine, manual impact machine and other complete sets of equipment. Our company's technology has made the following explanation of the cantilever beam impact testing machine:

The domestic measurement of the impact strength of plastics is generally made of simple-supported beams.Impact testing machineand cantilever beam impact tester. The samples can be divided into two types: notchless and notched, and can be completed with automatic notched prototype and manual notched prototype. The impact resistance measurement with notched simulates the impact of the material in harsh environments.

During the impact experiment, the pendulum is hung on the frame's arms from a vertical position, and lifts the arms up and raises the angle α, and the pendulum obtains a certain position energy. Release the pendulum to let it fall freely. Push the spline placed on the bracket. When it rises in the reverse direction, push the pointer to read the power A consumed to break the sample from the dial reading, and then calculate the impact intensity:

b and d are the width and thickness of the sample respectively. For the sample with notch, d is the thickness remaining for removing the notch. The value read from the dial is the work consumed for impacting the sample, which also includes the "flying work" of the sample, expressed in relation to:

W is the weight of the pendulum, L is the length of the pendulum, and α and β are the angles of the rising before and after the impact of the pendulum; A is the power consumed by the impact sample; Aα and Aβ are the power consumed by the pendulum to overcome air resistance within the angles of α and β; it is "flying work", and it is generally believed that the last three terms can be ignored, so it can be abbreviated as:

For a fixed instrument, α, W, and L are all known, so the reading disk can be drawn according to the size of β and the power consumed by the impact sample can be directly read out. In fact, the fly-out part varies greatly due to different test instruments and different conditions, and sometimes even accounts for 50% of the reading A. Fresh materials often have great flying skills, and thick samples have greater flying skills than thin samples. Therefore, when the test conditions are different, the numerical values ​​are often difficult to quantitatively compare, and only the same material and the same measurement conditions are suitable.

The energy absorbed by the sample breakage seems to be an area phenomenon on the surface. In fact, it involves how large the volume involved in the absorption of impact energy is, which is a volume phenomenon. If a material produces chain segment movement under a certain load (yield strength), thereby increasing the number of chain segments involved in bearing external forces, that is, increasing the volume of the impact energy involved in absorbing impact energy, then its impact strength will be greater.

Brittle materials are generally fractured, while tough materials are mostly irregular fractures, which will turn white near the fracture, and the volume involved is larger. If the tough material continues to crack after impact but has been destroyed, the impact strength is expressed as "continuous".

More AboutImpact testing machineAll relevant information is available in Jinan Hengsi Shanda Instrument Co., Ltd.