© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Nitriding and Ferritic Nitrocarburizing in the VDR(N) Furnace
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR Specifications
2
Sizes: M & XL
§ Load dimensions (W x L x H): § M: 24” x 36” x 24” § XL: 36” x 48” x 36”
§ Temperature up to 1,382 ºF (750 ºC) § Gas or electrical heated
§ HydroNit® sensor measures the hydrogen content § Provides control of the nitriding
potential (KN-control) § Nitro-Prof ® control software utilizes
process data acquisition § Pronox® offers post-oxidation control
Controls
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR Components
3
Vacuum Pump System
Heating Elements
Housing
Thermal Post-Combustion
Retort
Indirect Cooling System Hot Gas Blower – Inside Retort
Hot Gas Blower
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR Components
4
Gas Panel
Housing High-Speed Cooling System
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR(N) Benefits
5
Uniformity: § Gas circulation within the retort
can be optimized through increased efficiency and improved directional flow § Excellent temperature uniformity: ±10 ºF (±5 ºC)
Versatility: § High quench intensity with new
shut-off flaps on the cold and hot side of the cooling stream
Speed: § Cycle time reduced by up to 30%
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR: Temperature Uniformity
6
§Gas flow optimization within the retort §Heat transfer
improvement reduces the temperature difference within the load § The VDR furnace has
an excellent temperature uniformity of ±10 ºF (±5 ºC)
1060
1065
1070
1075
1080
1085
1090
Part 1 Part 2 Part 3 Part 4 Part 5 Part 6 Part 7 Part 8 Part 9 Part 10 Part 11
Tem
pera
ture
F
MeasurementSetpoint Temperature
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
More Speed = Greater Profit
7
0
200
400
600
800
1000
1200
0 2 4 6 8 10 12 14Time in hours
Tem
pera
ture
ºF
Furnace Time (8 hours) Saves 4 hours
Traditional
Multi Treater with
4,000-pound sample load: Ferritic nitrocarburizing for 4 hours at 1,060 ºF (570 ºC)
Traditional Retort Furnace
VDR with High-Speed Cooler
To produce 10-15mm white layer:
§ A conventional furnace requires 12 hrs.
§ The VDR furnace requires eight hrs.
§ The VDR furnace produces three batches/day instead of only two batches/day
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR: Atmosphere Control with HydroNit® Sensor
8
Goals: § Controlled layer structure generation § Reproducible layer structure and thickness § Minimal process duration
Requirements: § Measurement device for the continuous
monitoring of atmospheric component (e.g., H2)
§ Continuous monitoring of the input gases § Atmosphere and nitriding potential algorithm § Cracked ammonia or hydrogen for the
reduction of the nitriding potential § Automatic gas flow controller
Pressure Measuring
Protecting Tube
Measurement Tube
Furnace Wall
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR: Atmosphere Control with HydroNit® Sensor
9
Results: Using the HydroNit® sensor, process time and
gas consumption are reduced by up to 30 percent.
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Nitriding Cycle with Pre- and Post-Oxidation
10
Pre-oxidation C
ondi
tioni
ng
Nitriding
Post-oxidation
Heating Controlled Process
Cooling
Air
NH3
CO2
C3H8
H2O
Air
Evac
uatio
n
Fillin
g
N2 N2 up to 50% Total Gasing
NH3 up to 100% Total Gasing
H2O
N2
900°F-1020°F
840°F-970°F
570°F-750°F
Nitro-Prof
765 Torr
<30 Torr
765 Torr
<30 Torr
Pre-oxidation C
ondi
tioni
ng
Nitriding
Post-oxidation
Heating Controlled Process
Cooling
Air
NH3
CO2
C3H8
H2O
Air
Evac
uatio
n
Fillin
g
N2 N2 up to 50% Total Gasing
NH3 up to 100% Total Gasing
H2O
N2
900°F-1020°F
840°F-970°F
570°F-750°F
Nitro-Prof
765 Torr
<30 Torr
765 Torr
<30 Torr
(480 °C – 550 °C)
(300 °C – 400 °C)
(450 °C – 520 °C)
N2 up to 50% total gassing
NH3 up to 100% total gassing NH3
®
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
FNC Cycle with Pre- and Post-Oxidation
11
Pre-oxidation C
ondi
tioni
ng
Nitrocarburizing
Post-oxidation
Heating Controlled Process
Cooling
Air
NH3
CO2
C3H8
H2O
AirE
vacu
atio
n
Filli
ng
N2 N2 45% Total Gasing
NH3 50% Total Gasing
CO2 5% Total Gasing
H2O
N2
1020°F-1095°F
840°F-970°F
570°F-750°F
Nitro-Prof
765 Torr
<30 Torr
765 Torr
<30 Torr
Pressure
Pre-oxidation C
ondi
tioni
ng
Nitrocarburizing
Post-oxidation
Heating Controlled Process
Cooling
Air
NH3
CO2
C3H8
H2O
AirE
vacu
atio
n
Filli
ng
N2 N2 45% Total Gasing
NH3 50% Total Gasing
CO2 5% Total Gasing
H2O
N2
1020°F-1095°F
840°F-970°F
570°F-750°F
Nitro-Prof
765 Torr
<30 Torr
765 Torr
<30 Torr
Pre-oxidation C
ondi
tioni
ng
Nitrocarburizing
Post-oxidation
Heating Controlled Process
Cooling
Air
NH3
CO2
C3H8
H2O
AirE
vacu
atio
n
Filli
ng
N2 N2 45% Total Gasing
NH3 50% Total Gasing
CO2 5% Total Gasing
H2O
N2
1020°F-1095°F
840°F-970°F
570°F-750°F
Nitro-Prof
765 Torr
<30 Torr
765 Torr
<30 Torr
Pressure
(300 °C – 400 °C)
(550 °C – 590 °C)
(450 °C – 520 °C)
N2 (45% total gassing)
NH3 (50% total gassing) NH3
CO2 (5% total gassing)
®
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Pre-Oxidation and Oxinitriding: Improving Reaction Kinetics
12
§ Reduces the incubation time of nitride formation § Improves the uniformity of the
compound layer thickness § Increases the thickness of the
e-compound layer
Pre-oxidation Oxinitriding
480ºF-840ºF
1,080 ºF (580 ºC)
Purge phase
(e.g., N2)
Heating and Holding phase in Air
Heating and holding phase
in NH3
Holding phase with KN-control
t Heating and
holding phase in air
t
480 °F – 840 °F (250 °C – 450 °C)
Heating & Holding in NH 3 /
Oxidation agent
t
X5CrNi18 - 10 X90CrMoV18 X5CrNiMo17 - 22 - 2 X40CrMoV5 - 1
t
X5CrNi18 - 10 X90CrMoV18 X5CrNiMo17 - 22 - 2 X40CrMoV5 - 1
750 °F – 930 °F (400 °C – 500 °C)
Purge phase (e.g., N2)
Purge phase
(e.g., N2)
Heating phase in
NH3
Heating and holding
phase in NH3/agent
Holding phase in NH3 /carburizing
agent
Holding phase with
KN-control
Purge phase (e.g., N2)
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Pronox®: Corrosion Resistance Improvement
13
min. 15 µm e – compound layer
Base material
1 - 3 µm iron oxide layer Fe3O4
min. 8,6 % Nitrogen plus Carbon contentmin. 15 µm e – compound layer
Base material
1 - 3 µm iron oxide layer Fe3O4
min. 8,6 % Nitrogen plus Carbon content
Corrosion resistance
in salt spray test up to 400
hours!
1,020 ºF – 1,095 ºF (550 °C – 590 °C)
840 ºF – 970 ºF (450 °C – 520 °C)
t t Purge phase
(e.g., N2)
Heating phase in NH3
Holding phase in NH3 /carburization agent
Purge phase
(e.g., N2)
O2-control with air or H2O (Pronox®)
Heat Treatment Cycle:
Micrograph:
Load Image:
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Post-Oxidation Control Amount of oxygen will depend on: § Post-oxidation temperature § Load surface
Main reasons to control post-oxidation: § Heat treatment reproducibility § Optimized oxygen consumption
14
l Sensor position in the exhaust fume pipe
Therefore, only the optimized mV value with l
sensor is necessary.
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Post-Oxidation Summary
15
§Use of a low temperature: 840 ºF (450 °C) §Hydrocarbon addition at the end of the FNC
process §Cooling to post-oxidation temperature under
ammonia and hydrocarbon §Small difference between end of oxide layer
and maximum N+C value §Quenching after post-oxidation instead of slow
cooling
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
VDR Controls: NitroProf® 4.0
16
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Nitriding: Internal Gear
17
Material: 31CrMoV9V
Nitriding Temperature: 960 ºF (515 ºC)
Process Duration: 70 h
Nitriding Potential: 4 – 4.5
Nitriding Depth: 0.015” – 0.029”/0.018”
Compound Layer Thickness: Max 20mm/17mm
Specification/Results:
Process Printout: Microstructure:
Load Image:
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Material: 31CrMoV9V
Nitriding Temperature: 1,000 ºF (540 ºC)
Process Duration: 18 h
Nitriding Potential: 3
Surface Hardness: 720 – 820 HV10/758 HV10
Compound Layer Thickness: 14 – 22mm/16.2mm
FNC: Balance Pin
18
Specification/Results:
Process Printout: Microstructure:
Load Image:
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Material: 4140/42CrMo4
Nitriding Temperature: 1,060 ºF (570 ºC)
Process Duration: 5 h
Nitriding Potential: 2.5
Surface Hardness: 550 – 650 HV10/630 HV10
Nitriding Depth: 0.4 – 0.55 mm/0.5 mm
Compound Layer Thickness: 8 – 35mm/14.3mm
FNC: Inner Gear
19
Specification/Results:
Process Printout: Microstructure:
Load Image:
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Summary The advanced process and furnace technology of Ipsen’s VDR furnaces make it possible to create uniform, repeatable nitrided or nitrocarburized layers on a variety of materials. Benefits include: §Optimized uniformity of the hot gas flow and the
increased hot gas volume flow result in a temperature uniformity of ±10 ºF (± 5 ºC) § Reduction in process time by up to 30% thanks to the
VDR furnace’s new, external high speed cooler § Increase in throughput as components are treated for a
shorter span of time
20
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
Optimized Processes: §Nitriding §Oxinitriding §Nitrocarburizing
§Oxinitrocarburizing §Pre-oxidation §Post-oxidation
Process Monitoring and Control:
Summary (cont.)
21
§Gas-analyzers §Oxygen-probe §HydroNit® sensor
§KiNit sensor §Atmosphere calculation
model
© 2015 Ipsen
This document contains proprietary information of Ipsen. It is submitted in confidence, and may not be reproduced or used for any other purpose or disclosed to others without written authorization from Ipsen.
