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+ Mechanical Properties
Mechanical properties of MOSTUF T composite bearing is shown in Table 1. Fig. 2 shows the test device for the testing of load-deformation of MOSTUF T bearing in accordance with MIL-B-85560 specifications.
Generally, composite bearing accompanies permanent deformation in addition to the elastic deflection under radial load. This permanent deformation results from compaction between bearing layer and backing layer. Fig.3 shows the relation between elastic deflection and permanent set under radial load

< Table 1 > Mechanical properties of MOSTUF T composite bearing
Properties Units Values
Maximum compressive strength MPa 430
Static loading strength MPa 240
Radial rupture strength MPa 550
Hardness HRM 95
Density g/㎤ 2.0

< Fig 2> Typical static radial load test setup of MOSTUF bearing

< Fig 3> Permanent set and deflection of MOSTUF T bearing

+ Thermal Properties
Operating temperature of MOSTUF composite bearing is between -100~+160℃. And coefficient of thermal expansion is similar to the coefficient of thermal expansion of steel. So the bearing can exhibit its performance without separating from housing even though exposed extreme temperature change.

< Table 2> Coefficient of thermal expansion for Mostuf™ composite bearing, steel and aluminum
Units MOSTUF™ Bearing Steel Aluminum
Coefficient of thermal
expansion(25~150℃)
㎛/m℃ 13 x 10-6 11 x 10-6 24 x 10-6

+ Bearing Properties
< Table 3> Bearing properties of MOSTUF composite bearing
Units MOSTUF-T MOSTUF-P
Maximum load static MPa 240 140
dynamic MPa 140 35
Maximum sliding speed m/sec 0.2 2.5
Maximum PV value MPa x m/sec 1.8 2.0
Frictional coefficient(dry) - 0.03~0.12 0.03~0.08
Maximum operating temp 160 180
Minimum operating temp -100 -100

< Fig 4> Over view of bearing tester
+ Coefficient of Friction
The dynamic coefficient of friction for Mostuf composite bearing is between 0.03 & 0.12, depending upon loads, type of movement, sliding speed, operating temperature, micro finish of mating surface. Fig.5 shows the change of dynamic coefficient of friction under oscillating load. At the beginning of test, coefficient of friction is being kept up on steady-state conditions
< Fig 5 > Dynamic coefficient of friction of MOSTUF-T bearing
(Tested by Powertech Labs Inc., B.C, Canada)

+ Bearing wear
Bearing wear occurs due to many kinds of factors. Fig.6 shows the test results under bearing pressure of 60 MPa at room temperature. There shows rapid wear during initial thousands of cycles. During this period, there happens transfer of PTFE on the surface of shaft and redistribution of fiber on the sliding direction, resulting into smooth bearing surfaces. After some initial wear, wear rate shows steady progress.
Direct wear stays under 0.12mm after 256,000 cycles.
< Fig 6> Direct wear of MOSTUF-T bearing
(Tested by Powertech Labs Inc., B.C, Canada)

< Fig 7> shows the shaft and bearing after finishing all test cycles.
< Fig 8> shows contact area which was highly polished and journal contact surface had a significant amount of wear debris(lubricant film) adhering to the contact face.
< Fig 9> shows close up view of bushing center of contact surface. There did not appear to be any damage to the journal contact surface other than minor polishing.


+ Chemical Properties
MOSTUF composite bearing have resisting power to various kinds of chemical substances Also they have dimensional stability even after exposed into sea water or fresh-water for a long time
< Table 4 > Chemical resiatance of Mostuf -T bearing composite.
Alcohols Gases Acids(10%)
Methanol Butane Hydrochloric acid
Ethyl alcohol Ozone Boric acid
Allyl alcohol × Nitrogen Acetic acid
Butyl alcohol × Natural gas Sulphuric acids
Propyl alcohol Acetylene Nitric acids ×
Isopropanol Hydrogen Carbonic acids ×
Hydroxy aceton Fluorine × Hydrofluoric acid ×
Chlorine gas ×
Solvents Salts Alkalies(10%)
Aceton Sodium acetate Sodium hydroxide
Toluene Sodium carbonate Calcium hydroxide
Methyl ethyl keton Ammonium nitrate Ammonium hydroxide ×
Trichloroethane × Ammonium chloride Magnesium hydroxide
Benzene × Magnesium sulphate
Oils Fuels Others
Gear oil Kerosene Freon
Motor oil Jet fuel Formaldehyde
Hydraulic oil Diesel Sodium nitrate
Linseed oil Petroleum Ethylene glycol
  Sodium hydroxide Ammonia ×
100℃ water ×
○ resistant × non resistant