V 1% magne 
wg Mou of 
Method used © Microscopic investigations 
1 welgy of To explain this transformation behaviour microscopic investigations were carried out. The non- 
Ar tracks, uniform distribution of martensite on the worn surface was studied by profilometry and scanning 
Chösen to avoid electron microscopy. 
"88. Preliminary The profilograms of the wear tracks showed material transfer at such places where martensite was 
Ray found (fig. 3). This result was confirmed by SEM investigations [ 5]: The local differences of the 
magnetic measurements correspond to the distribution of wear particles in the wear track. Fig 4 
shows such a very thin platelet. Particles of the same shape are found in the debris (fig 5) and on the 
ALO; counterbody as well (fig. 6). Evidently, the particles are generated in consequence of the 
5 of magne plastic deformation of the sample surface, transferred to the counterbody and later on in the course 
of the friction process re-transferred to the sample surface. 
Tensite; 
a 20 
endence of the © 
or the Metastable E10 
ready at room , 
Ag temperature 3s | 
s. However, ths = 
ain temperature, 0 Ale. ; 
IRIE properties | 
-5 
0 2 4 8 
Distance along the track (mm) 
nei 1.4438 
Fig. 3: Steel 1.4439. Profile of the wear track Fig. 4: Steel 1.4958. Shape of a particle inside the wear 
track 
ae 
m W 
yaar track (°) 
neous (fig 22). 
temperature In 
Ib) also im these Fig. 5: Steel 1.4958. Shape of a debris particle Fig. 6: Steel 1.4958. Transfer particle on the counterbody 
her decrease of 
im general A section through the wear track shows the typical metallographic feature of tribologically stressed 
detected austenite (fig. 7): Immediately at the friction surface a destroyed zone is found. This zone exhibits a 
very homogeneous structure, however, no detail can be resolved. This layer is partly covered by 
transferred wear particles. Beneath the destroyed layer the material is plastically deformed. The 
degree of the plastic deformation decreases with the distance from the surface. This sequence of 
different deformation states can be confirmed by microhardness measurements. The Knoop 
375