NIST materials scientists Dan Fischer and Cherno Jaye
Titanium, a protean element with applications from pigments to aerospace alloys, could get a new role as an environmentally friendly additive for automotive oil, thanks to work by materials scientists from Afton Chemical Corporation and the National Institute of Standards and Technology. Researchers have established that a titanium compound added to engine oil creates a wear-resistant nanoscale layer bound to the surface of vulnerable engine parts, making it a credible substitute for older compounds that do not coexist well with antipollution equipment.
For years antiwear additives for high-performance oils have been phosphorous compounds, especially ZDPP, that work by forming a polyphosphate film on engine parts that reduces wear. Unfortunately phosphorus is a chemical poison for automobile catalytic converters, reducing their effectiveness and life span, so industry chemists have been searching for ways to replace or reduce the use of ZDDP.
Titanium is one candidate replacement. Mechanical tests of an organic titanium compound at Afton demonstrated that it provided superior wear resistance when added to a fully formulated engine oil, suggesting that oil chemists could use less ZDDP.
Measurements revealed that the antiwear enhancement comes from titanium chemically bound into the metal structure of the engine surface, forming a hard oxide, iron titanate…While considerably more work remains to be done, the results suggest that titanium could play an important role in future low-phosphorus lubricating oils.
Bravo! And an excellent example of profit and non-profit cooperative research.