Radio Frequency Division

Technology

Introduce IH Heat-Treatment

When you make the decision to use high-frequency hardening, you might think that there would be something like a user manual. There are various ways to classify the approach to high-frequency hardening, but on the basis of long years of experience, there are essentially three elements to consider: the hardening method, frequency, and capacity. This is only to give you a general idea and we hope that it will be of use to you.

Types of Hardening Methods

High-frequency hardening methods are generally divided into two: single shot hardening and traverse hardening.

Types of Frequencies

The hardening depth is dictated by the penetrating depth of the selected frequencies.

Apparatus Capacity and Items Typically Processed

Apparatus (oscillator) capacity is calculated according to the material, shape, range of hardening depth, heating time, and other factors.

Determining High-Frequency Hardening Specifications

Steel and Symbol Hardening hardness Maximum hardening depth (mm)
(for reference)
Pretreatment
A(water) B(oil)
HRC HV HS HRC HV HS (water)
Carbon steel machine structural components S35C 40-50 390-510 54-67 35-45 350-450 48-60 4.0 Refining
S40C 45-55 450-600 60-74 40-50 390-510 54-67
S45C 50-60 510-700 67-81 43-53 420-560 57-71 Refining or normalizing
S50C 55-62 600-750 74-85 45-55 450-600 60-74 5.0
S55C 58-63 650-770 78-87 50-60 510-700 67-81
Nickel chrome steel SNC236 45-55 450-600 60-74 40-50 390-510 54-67 6.0 Refining
SNC631 42-52 380-540 56-69 37-47 360-470 50-63
SNC836 50-60 510-700 67-81 45-55 450-600 60-74
Nickel chrome
molybdenum steel
SNCM439 50-58 510-650 67-78 45-53 450-560 60-71 8.0 Refining
SNCM447 55-63 600-700 74-87 50-58 510-650 67-78
Chrome steel SCr430 50-60 510-700 67-81 45-55 450-600 60-74 6.0 Refining
SCr435 50-60 510-700 67-81 45-55 450-600 60-74
SCr440 55-63 600-770 74-87 50-58 510-650 67-78
SCr445 55-63 600-770 74-87 50-58 510-650 67-78
Chrome molybdenum
steel
SCM432 50-60 510-700 67-81 45-55 450-600 60-74 8.0 Refining
SCM430 50-60 510-700 67-85 45-55 450-600 60-74
SCM435 52-62 540-750 69-85 47-57 470-630 63-76
SCM440 55-65 600-830 74-91 50-50 510-700 67-81
Heat resistant steel SEH3 50-60 510-700 67-81 45-55 450-600 60-74 - Refining
Stainless steel SUS430 30-40 300-390 42-54 25-35 270-350 38-48 - Refining or normalizing
US420 45-55 450-600 60-74 40-50 390-510 54-67
Carbon tool steel SK2 58-63 650-770 78-87 53-58 560-650 71-78 5.0 Refining or normalizing
SK5 58-63 650-770 78-87 53-58 560-650 71-78
SK7 58-63 650-770 78-87 53-58 560-650 71-78
Nodular graphite cast-iron/td> FCD55 50-60 510-700 67-81 45-55 450-600 60-74 - Annealing
Nodular graphite cast-iron FCD55 50-60 510-700 67-81 45-55 450-600 60-74 - Annealing
Pearlitic malleable cast-iron FCMP50 50-60 510-700 67-81 45-55 450-600 60-74 - Annealing

A is for simple shapes such as shafts and pins.

B is for complex shapes like housings and shift forks.

The numbers in the table above refer to complete hardening to eliminate structural inconsistencies in the surface in order to increase durability.

The hardening depth d to appropriately increase the fatigue limit is found by d=0.15D, where D is the diameter of the item being hardened.

< High-Frequency Heat Treatment Prototyping  >

Photo: High-Frequency Heat Treatment Prototyping

DKK can perform prototyping of high-frequency heat treatment. It is typical for high-frequency hardening (tempering) processing methods to vary according to the shape of the object being heated. That's why we perform hardening tests (prototyping) using actual high-frequency power supplies in order to select the most appropriate parameters for your hardening (tempering) application. The best processing method can be determined on the basis of these results. Please ask us about this service.

Test Apparatus

No. Apparatus name Output (kW) Frequencies (kHz) Heating method Stroke Drive
1 Vertical traverse hardening equipment 250 30・60・200 Single shot - traverse heating
(work moves)
800mm Electric
2 Vertical traverse hardening equipment 250 30・60・200 Single shot - traverse heating
(work moves)
500mm Electric
3 Vertical traverse hardening equipment 120 30・100・200 Single shot - traverse heating
(work moves)
800mm Electric
4 Vertical traverse hardening equipment 350 1〜10・20 Single shot - traverse heating
(work moves)
1000mm Electric
5 Crankshaft hardening equipment 250 10・20・30・50 Heating coil follower heating Electric
6 Single shot hardening equipment 250 10・20・30 Single shot heating (2-stage) 250mm Electric
7 Crankshaft hardening equipment 200 10・20・30 Heating coil follower heating (twin coil) Electric
8 Synthetic dual frequency traverse hardening equipment 200
250
3・6・10・20
200
Single shot - traverse heating (work moves) 1000mm Electric
9 Synthetic dual frequency traverse hardening equipment 400
500
3・6・10・20
200・400
Single shot - traverse heating (work moves) 1000mm Electric
10 Single shot hardening equipment 100 1〜3 Single shot heating 250mm Pneumatic
11 Crankshaft hardening equipment 250 10・20・30・50 Heating coil follower heating Electric
12 Vertical traverse hardening equipment 400 10・30 Single shot - traverse heating (work moves) 2000mm Electric
13 Denko-CARRIER HEATER 50 3 Continuous heating (work moves) Electric

Inspection Apparatus

No. Name Purpose Number of units
1 Solid spectrophotometer Analysis of sample properties 1
2 CNC three-dimensional analyzer Measurement of sample dimensions 1
3 Digital microscope Structural observation of samples (surface and section) 1
4 Sophisticated inserted metal microscope Structural observation of sample (section) 1
5 Magnaflux inspection apparatus/td> Crack inspection of samples 1
6 Vickers hardness tester Hardness testing of samples (section) 3
7 Micro Vickers hardness tester Hardness testing of samples (section) 4
8 Rockwell hardness tester Hardness testing of samples (section) 1
9 Infrared thermography Sample surface temperature measurement 2
10 Recorders Sample temperature, voltage, and other measurements 13
11 Cutting tools Sample cutting 9
12 Grinders Sample grinding and polishing 5

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TEL.+81-3-3216-1682
FAX.+81-3-3216-1669

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