Crack Your Design Engineer Interview with These Questions | Engineer’s Interview Blueprint

Landing a job as a Design Engineer requires not only technical expertise but also the ability to showcase your understanding of core engineering concepts during interviews.  

From stress-strain analysis to SFD and BMD diagrams, recruiters often look for candidates who can confidently answer both theoretical and practical questions.  

In this blog, we'll explore some of the most common interview questions asked for Design Engineer jobs and provide engaging, easy-to-understand answers to help you prepare effectively. 

Let’s get started  

1. What is Stress-Strain? 

Stress is the internal force per unit area within a material caused by an external load, while strain is the deformation or displacement per unit length that occurs in response to this stress. Stress is measured in Pascals (Pa), while strain is dimensionless. 

2. Draw a Stress-Strain Curve for Ductile Material and Explain it. 

The stress-strain curve for a ductile material, such as steel, shows how the material deforms under load. The curve consists of: 

• Proportional limit: Where stress and strain are proportional. 
• Elastic region: The material returns to its original shape when the load is removed. 
• Yield point: Permanent deformation begins. 
• Ultimate tensile strength: The maximum stress the material can withstand. 
• Fracture point: The material breaks. 

3. Differentiate Between Ductile and Brittle Materials. 

• Ductile materials (e.g., steel) can undergo significant deformation before breaking, showing high tensile strength and malleability. 
• Brittle materials (e.g., glass) fracture with little deformation, meaning they have lower ductility and tend to snap suddenly under stress. 

4. What Are the Units of Stress and Strain? 

• Stress: Measured in Pascals (Pa) or Newton per square meter (N/m²). 
• Strain: It is a dimensionless quantity, as it represents a ratio of change in length to the original length. 

5. If I Take Two Cantilever Beams, One Made of Aluminum and Another Made of Steel, Having the Same Cross Section and Length, Subjected to the Same Point Load, on Which Beam is Stress More? 

The stress would be the same in both beams if they have the same cross-section and are subjected to the same load. However, the aluminum beam would experience greater deformation due to its lower modulus of elasticity compared to steel. 

6. What Are SFD and BMD? 

• SFD (Shear Force Diagram): It shows how shear force varies along the length of the beam. 
• BMD (Bending Moment Diagram): It shows the variation of bending moment along the beam's length. 

7. Draw SFD and BMD for a Cantilever Beam Subjected to a Point Load at the End. 

For a cantilever beam with a point load at the free end: 

• SFD: The shear force is constant along the length of the beam. 
• BMD: The bending moment linearly decreases from the maximum at the fixed end to zero at the free end. 

8. What is Hooke's Law? 

Hooke's Law states that, within the elastic limit, the stress applied to a material is directly proportional to the strain produced. Mathematically: 

Stress = E × Strain, where E is the modulus of elasticity. 

9. Up to Which Point is Hooke's Law Valid in the Stress-Strain Curve? 

Hooke's Law is valid up to the proportional limit on the stress-strain curve, where the material behaves elastically. Beyond this point, permanent deformation occurs, and the material no longer obeys Hooke's Law. 

10. What is Mohr's Circle? 

Mohr's Circle is a graphical representation used in structural analysis to determine principal stresses, maximum shear stresses, and stress transformation for different planes within a stressed material. 

11. What is Principal Stress? 

Principal stress refers to the maximum and minimum normal stresses acting on particular planes where no shear stress is present. It helps engineers identify the most critical stress points in a structure. 

Conclusion: 

Preparing for a Design Engineer interview requires a solid understanding of fundamental engineering principles and the ability to explain them clearly.  

The insights shared in this blog will help you confidently tackle the most common design engineer interview questions and highlight your readiness for the role. 

With Skill-Lync's Post Graduate Programs, you'll build a rock-solid foundation in all these critical concepts, making you interview-ready in no time. Plus, our Career Experts offer hands-on support through mock interviews, resume workshops, LinkedIn profile optimization, and much more! 

Sign up for a FREE course demo today, and let’s start your journey toward landing that dream job!