plastic-brittle transition

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1. Introduction

Plastic materials are everywhere in modern life. They are being used for a variety of different applications, due to the wide range of properties they offer. However, one of the major drawbacks of many plastics is their brittleness. As a result, plastic parts often fail under high loading conditions, which can lead to expensive maintenance and replacement costs. In order to overcome this problem, researchers have developed a variety of different approaches in order to reduce the brittleness of plastics. One of the most commonly used techniques is the so-called brittleness transition, which involves changing the chemical composition and/or the processing conditions to reduce the materials’ brittleness and increase their ductility. In this paper, a brief overview of the brittleness transition phenomenon is provided, and the different types of brittleness transitions are discussed.

2. Definition of Brittleness Transition

The brittleness transition is the process by which a material changes from being brittle to ductile under certain conditions. Brittleness is defined as the tendency of a material to break suddenly or with extremely limited deformation upon application of mechanical stress. Ductility, on the other hand, is the ability for a material to deform under stress. In other words, a material which is ductile is able to withstand larger levels of stress before it fails. As such, the brittleness transition involves changing the material’s properties in order to reduce the possibility of fracture.

3. Types of Brittleness Transitions

There are a number of different techniques which can be employed to reduce the brittleness of materials. One of the most common techniques is by changing the chemical composition by adding special additives or using a different chemical process. For example, the addition of glass fibers to a polymer can improve its ductility, as the glass fibers are able to reinforce the polymer matrix. Another technique employed is by changing the processing conditions. For example, altering the rate of cooling, as well as other parameters such as the temperature and pressure may help to reduce the brittleness of a plastic material.

4. Applications

The brittleness transition phenomenon can be used for a variety of applications. One of the most common applications is in automotive components. For example, car bumper covers and hoods can be made from ductile polymers, which helps to reduce the risk of damage in case of an accident. Other applications include aerospace and electronics components, where the brittleness of a material can have an impact on the performance and overall reliability of the components.

5. Conclusion

In conclusion, the brittleness transition is a process by which materials change from brittle to ductile. There are a number of different techniques which can be employed in order to induce the brittleness transition, such as by changing the chemical composition or processing conditions. The brittleness transition phenomenon has a number of applications, such as in automotive and aerospace components, as well as in electronics components.

Plastic-brittleness transition is the process of attaining brittle properties in plastic materials due to the influences of external stress, temperature and environment. As temperature decreases and external stress increases, the plastic material also becomes more brittle. The brittleness of plastic materials can be related to the glass transition temperature (Tg) of the material, which indicates the temperature at which the polymer undergoes an infrared transition from a rubbery state to a glassy state. For some plastics, Tg can be determined using a combination of tests, but for others, it is determined by a more complex chemical analysis.

At temperatures below Tg, plastic materials become more brittle and can fail without visible signs of deformation. This phenomenon is called plastic-brittleness transition because below this temperature the plastic material can not back to its original form when deformation is relieved. This transition occurs due to the loss of mobility of the molecules, which cause them to lose the ability to re-order or restore themselves under load and thus become brittle.

In addition, the presence of fillers, plasticizers, and other admixtures can affect the plastic-brittleness transition temperature. For example, the addition of higher amounts of plasticizers tends to increase the plastic-brittleness transition temperature whereas the addition of fillers merely produce a decrease of Tg for certain compounds. Furthermore, additives such as antioxidants and plasticizers can create temperature effects that could increase the plastic-brittleness-transition temperature.

In conclusion, plastic-brittleness transition is a phenomenon in which plastics lose their flexibility and become brittle when exposed to certain environmental stress, temperature and external forces. The transition depends on the glass transition temperature of the material, and the presence of other admixtures such as plasticizers and fillers can also affect the transition temperature. Attention should be paid to the change in the environment, temperature and external stress in order to reduce the risk of the transition and maintain the ideal shape of the plastic material.