Induction Hardening for Crankshafts in Automotive Engines

Introduction: Building the Heart of Every Engine

That’s where induction hardening comes in. This advanced localized heat treatment process enhances the fatigue strength, wear resistance, and lifespan of crankshafts used in cars, tractors, and heavy vehicles.

At Thakur Induction, Ludhiana, we provide precision crankshaft hardening services for OEMs and industrial manufacturers across Punjab and North India, ensuring unmatched strength and performance.

Why Induction Hardening Is Ideal for Crankshafts

Crankshafts experience constant cyclic stress and torsional load. The surface of bearing journals and fillets must resist wear, bending, and fatigue while maintaining a tough, shock-absorbing core. Induction hardening provides the perfect metallurgical solution by hardening only the surface layer, leaving the core ductile for flexibility.

Key Advantages:

• Improved fatigue strength and torsional durability
• Increased wear resistance of journals and fillets
• Controlled case depth (1.5–3 mm) for optimized hardness
• Minimal distortion or warping after treatment
• Fast, energy-efficient, and repeatable process

💡 Every hardened layer means more revolutions per minute — with less wear per cycle.

The Induction Hardening Process for Crankshafts

At Thakur Induction, we use custom-designed coils and medium-frequency induction systems to precisely harden specific zones of the crankshaft — mainly bearing journals, pins, and fillets.

Step-by-Step Process:

1. Pre-Cleaning and Inspection: The crankshaft is cleaned to remove oil, rust, or scale for uniform heating.
2. Induction Heating: Using a medium-frequency electromagnetic field (10–30 kHz), the crankshaft surface is rapidly heated to 850–950°C.
3. Quenching: Immediate polymer or water quenching transforms the heated surface into hard martensite, achieving surface hardness up to 58–60 HRC.
4. Tempering (Optional): Tempering at 150–200°C relieves internal stress and improves structural balance.
5. Hardness and Case Depth Testing: Each crankshaft undergoes Rockwell hardness testing and microhardness inspection to verify uniformity.

🔍 Every journal and fillet receives precision heat treatment — micrometer by micrometer.

Materials Suitable for Induction Hardening Crankshafts

We adjust frequency, power, and quenching based on each steel’s metallurgical response.

Case Study: Crankshaft Hardening for Tractor Engine Manufacturer

• Surface hardness achieved: 59 HRC
• Fatigue life improved by: 35%
• Dimensional accuracy maintained: within ±0.05 mm

🏅 A perfect balance of strength, surface hardness, and precision — achieved through controlled induction.

Conclusion: Powering Performance with Induction Hardening

In today’s high-performance automotive world, precision heat treatment defines engine reliability. Through controlled induction hardening, crankshafts gain the strength to handle high torque, friction, and continuous stress — ensuring smooth power delivery and extended engine life.

At Thakur Induction, Ludhiana, we bring engineering excellence and metallurgical precision to every crankshaft we treat — powering Punjab’s automotive growth with technology and trust.