Effect of Speed and Pressure on Dry Sliding Interactions of Alumina against Steel

Abstract

Sliding of alumina (87%) pins against a hardened steel disk over a range of pressures (3.3-30.0 MPa) and speeds (0.1-12.0 ms-') has been studied. Four different regions (Rl, R2, R3, and R4) of friction as a function of speed have been identified. R l and R3 exhibit single-valued friction while in R2 and R4 the friction exhibits dual behavior. The speed range over which these regions prevail is sensitive to the pressure. R1 and R2 are low-speed and low-temperature regions, and in both, metal transfer and formation and compaction of y-Fe,O, occur. R3 and R4 are associated with high speeds and high interface temperatures. Formation of FeO, FeAI,O,, and FeAIO, has been observed. The implications of the tribochemical interactions on friction and wear characteristics are discussed.

TiN‐Particle reinforced alumina for unlubricated tribological applications mated with metallic counterbodies

“…Friction and wear reducing layers were built up by densifying of the wear particles. This was accompanied by tribo-chemical reactions such as formation of Fe 2 O 3 , FeO, Fe 3 O 4 or FeAl 2 O 4 , respectively [11,23,24]. In the contact area of the SSiC/steel-pairs, SiO x layers and silicides can be formed at higher temperatures [24].…”

Wear of ceramic and ceramic–metal composites in high-speed dry sliding over steel

“…At elevated contact temperatures, this layer exhibits low shear stability and acts as a lubricant [6]. Similar maintenance of high tribotechnical characteristics and protective properties of layers with secondary structures formed in the tribocontact area in high-speed friction were reported in the papers [7,8], which examined zirconia and alumina ceramics. It was established [8] that ZrO 2 -Y 2 O 3 ceramic samples showed high wear resistance at high sliding speeds (up to 34 m/sec) in spite of high temperatures in the tribocontact area and associated high-temperature phase transformations.…”

Wear behavior of zirconia-bazed ceramics under highspeed dry sliding on steel

“…At elevated contact temperatures this layer has low shear stability, playing the role of lubricant [6]. Similar cases of preserving high tribological characteristics and protective function of transfer layers formed in high-speed friction on steel have been discussed in [7,8], which consider zirconia-and aluminabased ceramic materials. According to [8], at high sliding speeds up to 37 m/s Y-TZP ceramic specimens demonstrate high wear resistance despite high temperatures in the tribocontact zone and related high-temperature phase transitions.…”