http://fluxtrol.com Computer simulation is used to predict the residual stresses and distortion of a full-float truck axle that has been induction scan hardened. Flux2D® is used to model the electromagnetic behavior and the power distributions inside the axle in terms of time. The power distributions are imported and mapped into DANTE® model for thermal, phase transformation and stress analysis. The truck axle has three main geometrical regions: the flange/fillet, the shaft, and the spline. Both induction heating and spray quenching processes have significant effect on the quenching results: distortion and residual stress distributions. In this study, the effects of spray quenching severity on residual stresses and distortion are investigated using modeling. The spray quenching rate can be adjusted by spray nozzle design, ratio of polymer solution and quenchant flow rate. Different quenching rates are modeled by assigning different heat transfer coefficients as thermal boundary conditions during spray quenching.

1. Effect of Spray Quenching Rate on Distortion
and Residual Stresses during Induction
Hardening of a Full-Float truck Axle
Zhichao (Charlie) Li, and B. Lynn Ferguson
DANTE SOFTWARE, Cleveland, OH 44130, USA
Valentin Nemkov, Robert Goldstein, and John Jackowski
Fluxtrol, Inc. 1399 Atlantic Blvd, Auburn Hills, MI 28326, USA
Greg Fett
Dana Corporation, 3939 Technology Drive, Maumee, OH43537,
USA
ASM HTS 2013, 27th Conference and Exposition
15 September – 18 September 2013, Indianapolis, Indiana, USA

2. Introduction
 Induction hardening involves multiple phenomena,
including: electromagnetic, thermal, metallurgical,
stress and deformation.
 Flux software (electromagnetic and thermal
capabilities) is coupled with DANTE (thermal, phase
transformation, stress and distortion capabilities).
 Case chosen for study is a full-float axle, dimensions
typical for axles manufactured and hardened by Dana
Corporation.
 This study is a follow-up of the work presented at HES
2013, Padua, Italy.
 Effect of spray quenching rate on residual stresses and
distortion.
Slide 2

3. Mutually Coupled Phenomena in
Induction Heating Process
Slide 3

4. Axle Geometry and FEA Model
 Material: AISI 1541.
 Shaft dimension:
•
•
•
Length: 1008 mm.
Diameter: 34.93mm.
35 spline teeth.
 Single tooth model with
cyclic symmetry BC.
 FEA Meshing.
•
•
47746 hexahedral
elements.
16038 tetrahedral
elements.
Slide 4

5. Phase Transformation
 Diffusive transformation
 Martensitic transformation
Material: AISI 1541
Slide 5

6. Two-Turn Inductor Coil Design and
Flux2d Modeling
Full assembly of a two-turn axle
scan coil with quench body
Fillet area of axle modelled with
Flux 2D, mesh elements
Slide 6

7. Process Cycle
 Spray quench is 25.4 mm below the inductor.
 Spray quenchant: 6% polymer solution.
 Severity of spray quench (heat transfer coefficient):
•
Aggressive: 25,000 (W/m2C).
•
Medium:12,000 (W/m2C).
•
Mild: 5,000 (W/m2C).
Slide 7

8. Power Distribution in Three Regions
Modeled by Flux2D
Fillet
Shaft
Spline
Slide 8

9. Power Mapping from Flux2D to DANTE
 Good agreement on the temperature distributions predicted
by Flux2D and DANTE.
•
The power mapping from Flux2D to DANTE is valid.
Temperature
Predicted by Flux2D
Temperature
Predicted by DANTE
Slide 9

10. DANTE Results in Radius and Flange
At the End of 9 Second Dwell
Temperature
Austenite
Hoop Stress
Radial Disp.
Axial Disp.
Slide 10

11. DANTE Results in Radius and Flange
At 16.5 Second during IH Process
Temperature
Austenite
Hoop Stress
Radial Disp.
Axial Disp.
Slide 11

12. DANTE Results in Radius and Flange
At 130.15 Second during IH Process
Temperature
Austenite
Martensite Hoop Stress
Axial Disp.
Slide 12

13. Animation: IH Process HTC=12,000 W/m2C
13

14. Animation: IH Process HTC=5,000 W/m2C
14

15. Animation: IH Process HTC=25,000 W/m2C
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16. Axial Residual Stresses
Effect of Spray Quenching Rate
Unit: MPa
Slide 16

17. Hoop Residual Stresses
Effect of Spray Quenching Rate
Unit: MPa
Slide 17

18. Axial Displacements
Effect of Spray Quenching Rate
Unit: mm
Slide 18

19. Evolution Plots at the Cross Section
Effect of Spray Quenching Rate
 The cross section selected is 614.15 mm from the
flange end.
 Four points are selected to plot the process evolution.
•
•
Temperature, phase, stress, and displacement.
Depth of the four points: 0.0mm, 3.99mm, 8.12mm, 17.47mm.
Slide 19

20. Temperature and Phase Plots
Heat Transfer Coefficient (12,000 W/m2C)
20

21. Axial Stress and Displacement Plots
Heat Transfer Coefficient (12,000 W/m2C)
21

22. Temperature and Phase Plots
Effect of Cooling Rate
22

23. Axial Stress and Displacement Plots
Effect of Cooling Rate
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24. Summary
 Electromagnetic modeling by Flux and thermal/stress
modeling by DANTE were successfully coupled.
 The effect of spray quenching severity on residual
stresses and distortion are predicted.
 Higher spray rate increases the magnitudes of surface
compression, core tension, as well as the length growth.
 The modelling procedure developed in this study is
promising for design optimization, in-process failure
prevention, and service property prediction.
 Next step: tempering process modeling; loading model
with residual stresses; comparing with low cycle and
high cycle fatigue life experiments.
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