In which of the following situations would brittleness be most UNDESIRABLE?

Explanation:

Brittleness in Materials

Definition: Brittleness is a property of materials that causes them to break or shatter without significant deformation when subjected to stress. Brittle materials absorb very little energy before fracture, making them susceptible to sudden catastrophic failure.

Correct Option Analysis:

The correct option is:

Option 2: In tools that need to withstand heavy impact.

Brittleness would be most undesirable in tools that need to withstand heavy impact. Tools such as hammers, chisels, or any equipment used in construction and manufacturing processes are frequently subjected to heavy impacts and stresses. If these tools were made of brittle materials, they would be prone to breaking or shattering upon impact, posing a significant safety risk to users and potentially causing damage to workpieces. Therefore, materials with high toughness and the ability to absorb impact without fracturing are preferred for such applications.

Additional Information

To further understand the analysis, let’s evaluate the other options:

Option 1: In materials used in high-speed applications.

In high-speed applications, materials are required to have high strength and durability, but brittleness is not necessarily the most undesirable property. Depending on the specific application, materials can be designed to accommodate stresses and strains at high speeds. For instance, in some high-speed machinery, components might not experience heavy impacts but rather continuous and uniform loads, where brittleness might not be as critical a concern as in tools subject to heavy impact.

Option 3: In structural beams under static load.

Structural beams under static load primarily need to have high strength and the ability to bear loads without excessive deformation. While brittleness can be undesirable, it is not the most critical factor in this context. Ductility and strength are more critical properties for structural beams to prevent sudden failure and to ensure the structure can support loads safely over time. The primary concern would be the beam's ability to withstand static loads without excessive deflection or failure, rather than the impact resistance.

Option 4: In materials exposed to high temperatures.

High temperatures can affect the mechanical properties of materials, but brittleness is not the sole concern. Materials exposed to high temperatures must maintain their strength, thermal stability, and resistance to thermal expansion. While brittleness at high temperatures can be problematic, it is typically addressed by selecting materials that resist thermal degradation and maintain ductility and toughness even at elevated temperatures.

Conclusion:

Understanding the importance of material properties such as brittleness in different applications is crucial for ensuring safety and functionality. In the context of tools that need to withstand heavy impact, brittleness is highly undesirable because it can lead to sudden and catastrophic failure, posing significant safety risks. In other applications, such as high-speed machinery, structural beams under static load, and materials exposed to high temperatures, brittleness can be managed or is less critical compared to other material properties like strength, ductility, and thermal stability.