Activity lines:

1
Activity lines
Physical-Technical Institute of National Academy
of Sciences Belarus, Minsk
http//www.phti.belhost.by
?-mail phti_at_tut.by Tel/fax [phone])
Founded - 1931 Personnel- 370
Laboratories- 30
1. New materials for machine building
2. New technologies for thermal and deformation
processing of materials
2
Physical-Technical Institute of National Academy
of Sciences, Belarus, Minsk
Presents one of the investigation lines
3
Investigation and optimization of iron
deformability
Physical-Technical Institute of National Academy
of Sciences, Belarus, Minsk
Artur Pokrovsky
(Example of unusual action on traditional
material)
4
Iron, classical approach

• Excellent casting material
• Hardly deformable
• Material only for non-critical items

New view on iron

• Deformed iron enters the class of materials of
  high quality
• Has superior properties
• 3. Its area of applications is wider

5
Iron benefits as compared to steel

1. Higher thermal conductivity results in rapid heat
   sink (cylinder sleeves, guide valve sleeves)
2. Antifriction properties (camshafts, crank shafts,
   piston rings)
3. Quicker damping of vibrations and sounds (valve
   pushers)
4. Lighter by 10 (casings, pallets)

6

• Drawbacks of iron
• Low mechanical properties
• Casting defects degrading the properties

7
Traditional means of increasing mechanical
properties of iron

• Alloying
• Modifying
• Thermal treatment
• Quality of a casting,
• Casting defects
• Problems do not vanish

8
Advantages of deformation processing
3. Accuracy of shaping
2.Increase of strength characteristics
1.Guaranteed quality of metal
9
Why we turn to deformation of iron
Physical-Technical Institute of National Academy
of Sciences, Belarus, Minsk

• Casting defects such as pores and cavities are
  avoided
• Mechanical properties are enhanced up to the
  level of alloyed steel
• (strength is 1200 MPa, elongation 15)
• Antifriction characteristics are increased by a
  factor of 1.5

10
Control of graphite shape Traditional approach

• Change of graphite shape
• from branchy to compact
• and spherical ones

11
Control of graphite shape on deforming

• And vice versa,
• from spherical
• shape to fibers

12
We tested the following classes of irons
Gray iron
Mottled iron
Malleable iron
High-strength iron
And have found the most ADVANTAGEOUS ONES
13
Problems
Temperature parameters of deforming

• Steel 1200 800?? (? 400??)

• Irons 950 850?? (? 100??)

14
Temperature parameters
15
There are 5 groups of know-how
Conditions of iron deforming

1. Alloying diagrams
2. Preliminary thermal treatment for
   improvement of deformability
3. Design of press-forging tool
4. Temperature-force parameters of deforming
5. Finishing thermal treatment

16
Example of deliberate selectionof parameters for
iron deforming
Part body of drill chuck
Press forging from a solid billet FOR ONE STROKE
17
Example of violating the iron deforming
conditions
Part Cylinder of jack plunger for MAZ truck
Spoiled product (press-forging temperature
is violated)
High-quality semi-finished product
Finished part
18
Schematic diagram of iron deforming
1 Iron billet heated to high temperature 2
Body of press tool 3 Intermediate medium 4 -
Punch 5 Die 6 - Guide bush
19
Making the samples for investigations
Longitudinal samples
Incomingcasting billet
Transverse samples
Press-forged rod
20
Wearing weight loss during dry friction, deformed
condition (Decrease by a factor of 1.5 as
compared that in casting condition)
In order of decreasing wear resistance 1.
Mottled iron, (MtI) 2. High-strength iron,
(HSI) 3. Malleable iron, (MI) 4. Gray iron, (GI)
21
Significant feature of deformation is anisotropy
of structure and properties
Longitudinal section
Cross section
22
Anisotropy of wear during dry friction

• The selection is made
• of optimum relationships between
• Deformation
• parameters
• Microstructures
• Friction directions

Longitudinal sample
Transverse sample
23
Dry Friction Coefficient of friction can be
decreased by a factor of 2.5

Longitudinal sample
Transverse sample
24
Probable factors that cause improvement of
deformed ironcharacteristics

• Refinement of austenite grain
• Change in pearlite morphology
• Change in graphite morphology
• Origination of new graphite
• inclusions

25
1. Refinement of austenite grain
Grain number 3-4
Grain number 8-9
26
2. Changes in pearlite morphology
? 10000
? 10000
? 15000
27
3. Changes in graphite morphology
28
4. Formation ofnew graphiteinclusions
29
Industrial testing ofdeformed iron
Physical-Technical Institute of National Academy
of Sciences, Belarus, Minsk
Various parts have been offered but the greatest
interest has been shown in
2 lines (that will be discussed below)
30
High-quality billets of pistonand sealing rings
made from deformed iron
Physical-Technical Institute of National Academy
of Sciences, Belarus, Minsk

• Their mechanical properties
• are 2 times higher than those of cast
  rings
• Any failures are absent
• 7-fold decrease of lubricant bleeding
• No wear increase of mating part
• Stable and one and the same quality throughout
  the whole height

31
Appreciation in Belarus and Russia
32
High-quality billets of gears made from deformed
iron
Physical-Technical Institute of National Academy
of Sciences, Belarus, Minsk

• Strength is at the level of alloyed steel
• Noise in trucks is lower by 3 to 4 db
• Weight of gears is lower by 9 (the economy for
  one set is 700 g)

33
Disadvantages of technology

• High power requirements. A billet is to be
  heated.
• Some time is required for designing, fabricating
  and adjustment of press-forging tool.
• Costly press tool.
• Economically sound are
• Both mass production from 50 thousand pc
  per year (e. g., gears for MAZ) and piece
  production
• (e. g., piston rings Formula-1).

34
Present-day investigationproblems

• 1. Technological directional thrust is ahead of
  fundamental knowledge.2. The factors that cause
  iron hardening are still not completely cleared
  up.3. The role played by structure factorsin
  hardening is ambiguous.

35
We are in search of potential partners for

• Performing joint scientific investigations
• Cooperation in delivering billets made from
  deformed iron.

36
From the scientific viewpoint we are interested
in

• Physical factors and mechanisms responsible for
  iron hardening during hot deformation
• Computer simulation of iron hardening processes
• Tribotechnical tests
• Investigation of iron physical characteristics
• Construction of mathematical models of structure
  formation
• Investigation of fine structure (dislocations and
  point defects).

37
From the practical viewpoint we are interested
in

• Widening the area of deformed iron use as an
  effective competitive alternative to steel roll
  stock for manufacturing automotive and
  machine-building parts
• Joint realization of our technological
  developments during production of items from
  deformed iron with improved characteristics
• We are now prepared to produce rods for
  investigations as well as gear and sealing ring
  billets of various typical sizes

38
Contacts

• Physical-Technical Institute of National Academy
  of Sciences of Belarus
• 10 Kuprevich St., Minsk, 220141, Belarus
• Artur I. Pokrovsky, Cand. Tech. Sci.,
• Leading Scientific Worker
• Tel. [phone]
• ?-mail arturu_at_tut.by

39
Thank you for attention!