This document discusses induction hardening, which is a process where steel is hardened by induction heating and quenching in water. It works by placing the part to be hardened inside an induction coil through which alternating current is passed, heating the part. The heated part is then quickly cooled via quenching to harden it. Key factors that influence the hardness and depth of penetration include the composition of carbon in the steel, holding temperature and time. Induction hardening is commonly used to harden surfaces and is advantageous as it allows for localized and controlled hardening at high speeds.

1. Heat Treatment
Induction Hardening
By :
Afmardi
Ibnu Fajri

2. Induction Hardening
What is induction hardening?
Induction hardening is a process where steel is
hardened by means of induction heating
and subsequent quenching in water.

3. Basic of Principles
Induction hardening works by placing the
part to be hardened inside an "applicator" coil
of one or more turns, through which
alternating current is passed. The coil, which
in the case of gears and sprockets is round,
is usually made of copper tubing which has
water passing through it to prevent the coil
from overheating. The piece to be hardened is
rotated within the applicator coil. At JP
Engineering multiple pieces are hardened at
the same time by placing the sprockets or
gears onto a rod and then rotating the rod,
heating the parts and then feeding the rod
downward into the quench water.

4. The Depth of Penetration
For T = 20°C
f
dc
= 20
FFoorr TT == 880000°° CC
f
dh
= 500

5. Frequency
distance
Power supply Frequency
(KHz)
Depth of
Penetration
min (mm)
Diameter of
material
min (mm)
Medium Rotary
converter
0,5 - 10 1,5 15
High Valve
generator
100 - 500 0,2 1,5

6. Change Of Materials
d t t = 0,2
Where d = The Depth of
Penetration
t = time

7. Major uses of induction heat
treatment
• Melting ferrous and non - ferrous metals with
temperatures up to 1800 0c.
• Heating for forging up to 1250 0c.
• Stress relieving and normalizing steels after cold
forming between 750 0c and 950 0c.
• Surface hardening of steel or cast iron workpieces
at 850 0c to 950 0c.
• Soft soldering and brazing up to 1100 0c.
• Recrystallisation.
• Tube and Pipe Welding.

8. Procedure of Work

9. Continue……

10. Factor of Influence to Induction
Hardening
• Composition of Carbon
• Temperature
• Time Holding

11. Chart of Induction Hardening

13. Advantage of Induction Hardening
• Localised hardening of tooth surfaces where
hardness is needed
• Hardened teeth are pre-work hardened.
• Speed of hardening
• Depth of hardness is easily controlled
• Selected parts of the workpiece can be
heated.
• Heating time and temperature can be
precisely controlled.
• There is no smoke or soot pollution;

14. Continue….
• Heating operation can be integrated
in semi - automatic production
sequences;
• Induction equipment can usually be
operated by unskilled personal
• Very fast partial hardening;
• High production rates;
• Significant reduction in pollution,
distortion, forging scale, energy and
space requirements;
• High degree of reproduction and
automation;

15. Example Product of Induction Hardening

16. Microstructure of AISI 1045

17. Structuremicro of AISI 4140

18. Structuremicro of AISI DF2

19. Hardening of AISI 4140

20. Hardening of Materials

21. Thank You