Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
1
ADI JS/800-10 in substitutionof Nitrided EN-GJS 700-2 forprecision Planetary Gearbox
Dr.-Ing.Franco Concli
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
2
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
3
Ring gear
Centering (Output)Output flange
Bearing seat
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
4
EN 1563:2011 𝑹𝑴 [MPa] 𝑹𝑺 [MPa] A% [-] HV
EN-GJS-700-2 700 420 2 284-237
EN-GJS-700-2 Nit-Ox 700* 420* 2 450-520
Casting Rough machining Broaching Heat treatment Finishing
HV>450
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
5
EN 1564:1997 𝑹𝑴 [MPa] 𝑹𝑺 [MPa] A% [-] HV
EN-GJS-800-8 800 500 8 260-320
EN-GJS-1000-5 1000 700 5 300-380
EN-GJS-1200-2 1200 850 2 340-440
EN-GJS-1400-1 1400 1100 1 380-480
Casting Rough machining Broaching Finishing
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
6
Hub
Tooth
Root
Tip
Rounding(trochoid)
Tip circle
Root circle
Flank(circle evolvent)
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
7
Failure Type Effect
Bending Fatigue Catastrophic
Pitting Chafing fatigue Acceptable ?
Micropitting Chafing fatigue Acceptable ?
Scuffing Local welding (failure of the lubricant) Progressive damaging
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
8
Failure
Bending
Pitting
Micropitting
Scuffing
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
9
Failure
Bending
Pitting
Micropitting
Scuffing
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
10
Failure
Bending
Pitting
Micropitting
Scuffing
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
11
Failure
Bending
Pitting
Micropitting
Scuffing
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
12
Calculation of tooth bending strength
FN
2
cos6
1
cos
Fn
anFabnf
MAX
Sb
hF
W
M
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
13
Calculation of tooth bending strength
FPF
XlTRlT
F
NTSTFFP YYY
s
YY
ReRe
min
lim
Tooth root stress Permissibile bending stress
FFVA
n
tSaFaF KKKK
mb
FYYY
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
ADI DAYS 2016 6th – 7th October Minerbe
Calculation of tooth bending strength
FPF
FFVA
n
tSaFaF KKKK
mb
FYYY
XlTRlT
F
NTSTFFP YYY
s
YY
ReRe
min
lim
Tooth form factor(outer point of single contact)
Stress correction factor(notches)
Helix angle factor Application factor
Dynamic factor (tollerances)
Load factors(uneven load distribution)
Austempering, A Technology for Substitution
14
Tooth root stress Permissibile bending stress
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
15
Calculation of tooth bending strength
FPF
XlTRlT
F
NTSTFFP YYY
s
YY
ReRe
min
lim
Life factorStress correction factor = 2
Sensitivity factors
Size factor
Tooth root stress Permissibile bending stress
FFVA
n
tSaFaF KKKK
mb
FYYY
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
16
Calculation of tooth bending strength
Nominal stress EXPERIMENTAL
FPF
XlTRlT
F
NTSTFFP YYY
s
YY
ReRe
min
lim
Tooth root stress Permissibile bending stress
FFVA
n
tSaFaF KKKK
mb
FYYY
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
17
Calculation of surface durability
u
u
db
F
EE
p tH
1
cossin
2
11
1
1
2
2
2
1
2
1
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
18
Calculation of surface durability
HPH
HHVAt
EHH KKKKu
u
db
FZZZZ
1
1
XWVRL
H
NHHP ZZZZZ
s
Z
min
lim
Contact stress Permissibile contact stress
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
19
Calculation of surface durability
HPH
HHVAt
EHH KKKKu
u
db
FZZZZ
1
1
XWVRL
H
NHHP ZZZZZ
s
Z
min
lim
Contact ratio factor
Helix angle factor Application factor
Dynamic factor (tollerances)
Load factors(uneven load distribution)
Elasticity factor
Zona factor(Herzian pressure)
Contact stress Permissibile contact stress
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
20
Calculation of surface durability
HPH
HHVAt
EHH KKKKu
u
db
FZZZZ
1
1
XWVRL
H
NHHP ZZZZZ
s
Z
min
lim
Roughness factorLife factor
Velocity factor
Size factor
Work hardening factor
Lubricant factor
Contact stress Permissibile contact stress
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
21
Calculation of surface durability
HPH
HHVAt
EHH KKKKu
u
db
FZZZZ
1
1
XWVRL
H
NHHP ZZZZZ
s
Z
min
lim
Allowable stress number EXPERIMENTAL
Contact stress Permissibile contact stress
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
22
Toot bending strength characterization
F ⊥ flank: property of the circle evolvent
t
F R=0.1
W3
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
23
Toot bending strength characterization
Fixed part
Moving part
Movingpunch
Fixedpunch
Pin: centering
W3
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
24
Toot bending strength characterization
42
44
46
48
50
1 2 3 4 5 6
F [
kN
]
Test No [\]
Results of the Bending Test - ADI grade JS 800-10
Failure RunOut
Dixxon
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
25
Surface durability characterization
Motor
Actuator
Slave gearbox Gears on test
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
26
Surface durability characterization
1,0E+04 1,0E+05 1,0E+06 1,0E+07 1,0E+08 1,0E+09
N1 (-)
Results of Pitting Test - ADI grade JS 800-10
FailureRunout50% failure probability10% failure probability90% failure probabilityAGMA 939-A07 for HBW 310AGMA 939-A07 for HBW 250
Running in Test
T1 (Nm) 100 200-280
w (rpm) 1500 3000
q (°C) 60 60
ADI JS/800-10 in substitution of Nitrided EN-GJS 700-2 for precision Planetary Gearbox
Austempering, A Technology for Substitution
ADI DAYS 2016 6th – 7th October Minerbe
27
Conclusions
Experimental test were preformed on ADI JS/800-10 gear samples.
ADI JS/800-10 results comparable in terms of tooth root bending strength as well as surface durability withthe EN-GJS 700-2 nitrided cast iron and suitable for gear applications.
The low distortion induced by the austempering treatment, allows to reduce or avoid a further machining.
Eventual finishing operations are made on a low-hardness material: this implys faster and cheaperoperations