Page 328 - Handbook of Materials Failure Analysis

7 Severe Sliding Wear Particles 325

(a) 100µm (b) 100µm

200 µm 200 µm
(c) (d)
FIGURE 13.17
The fatigue wear particles with different color oxide films (200 ): (a) a fatigue wear
particle with yellow oxide film; (b) a fatigue wear particle with partial dark blue oxide film;
(c) a fatigue wear particle with partial dark oxide film and partial red oxide film; (d) a
fatigue wear particle with dark oxide film.

Figure 13.22c was a severe sliding wear particle from the Case Study 1. The big and
deep striations with the feature of torn from adhesive indicate the severe adhesive
wear. Figure 13.22d was another severe sliding wear particle from an oil sample
taken from a rolling element bearing lube in a Yankee machine. The deep striations
and the blue color suggest high temperatures were in situ.

CASE 3: THE SEIZURE FAILURES OF A BULLDOZER DIESEL ENGINE
A bulldozer diesel engine suffered a seizure failure. The bulldozer owner suspected
that the engine was deliberately sabotaged by a third party, so an oil sample was
taken from the engine oil sump for an investigation. Visual inspection found 70%
of free water in the oil sample. However, oil analyses excluded that the water was
from the coolant leaking. Wear particle analysis uncovered the catastrophic wear.
Figure 13.23 displays the catastrophic wear particles from the oil sample. As
the lubrication region was destroyed by the water, adhesive wear occurred.
Figure 13.23a and b were the severe sliding wear particles, featuring the deep stri-
ations on the particle surfaces. Figure 13.23c was a fatigue wear particle (L180 μm)
with partial straw-yellow oxide film. Figure 13.23d was a copper alloy fatigue wear
particles with the colorful oxides. The oxides on the particle surfaces indicate the
high in situ temperatures during particle generation.