Lube-Tech PUBLISHED BY LUBE: THE EUROPEAN LUBRICANTS INDUSTRY MAGAZINE
Crucially, Garkunov and his followers believed that both hydrogen wear and wearlessness could occur under the same operating conditions—but with very different outcomes depending on the materials and chemistry involved. If the surface lacks a protective tribofilm, hydrogen wear dominates. But if the right conditions are created—such as the presence of certain metal ions, like copper—a self-sustaining film can develop that blocks hydrogen ingress and suppresses wear almost entirely.
Viewed through this lens, the typical contributors to WEC formation—mechanical stress, electrical discharge, and tribochemical degradation—are not separate root causes. Rather, they are interconnected symptoms of a deeper process driven by the electrochemical behaviour of hydrogen in the friction zone. The contact zone becomes a kind of micro-reactor, where mechanical energy, electric current, and tribochemistry combine to drive destructive or protective outcomes depending on the chemistry at play.
No.159 page 4
chemistry is not designed to counteract hydrogen wear, subsurface damage may occur.
What makes Garkunov’s theory so compelling today is that it bridges the divide between the two dominant hypotheses for WEC formation—mechanical fatigue versus hydrogen embrittlement—and unites them within a single framework. It explains why WECs can occur even when conventional fatigue indicators are absent. And it suggests that by modifying lubricant chemistry—specifically, by promoting protective tribofilm formation and preventing hydrogen diffusion—we may finally have a way to stop WECs at their source.
Putting it to the test: Simulating electrically induced WECs To validate the hypothesis that copper-based lubricant additives could suppress the formation of White Etching Cracks (WECs), the research team designed a controlled laboratory test capable of closely replicating the tribological, thermal, and electrical conditions under which WECs are known to form in real-world machinery.
Figure 7: Combined Effects Chart
This integrated view helps explain modern reliability issues. In wind turbines, for instance, bearings are exposed to variable loads, transient contact conditions, and stray electrical currents from the generator system. These are precisely the ingredients for hydrogen generation and ingress. Likewise, in rail applications, regenerative braking introduces electrical discharges that pass through axlebox bearings. In both cases, the machinery may appear to be operating within mechanical specifications—but if the lubricant
32 LUBE MAGAZINE NO.188 AUGUST 2025
At the core of the experiment was a modified three-ring-on-roller tribometer, built around the Micropitting Rig (MPR) developed by PCS Instruments. For this study, the standard rig was significantly upgraded to enable electrically induced WEC testing—a relatively new and complex area of tribological simulation.
Figure 8: Modified MTM
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64
