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Jones, W. R., Jr.

Publications and source records attributed to Jones, W. R., Jr..

80 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Friction, wear, and thermal stability studies of some organotin and organosilicon compounds

Thermal decomposition temperatures were determined for a number of organotin and organosilicon compounds. A ball-on-disk sliding friction apparatus was used to determine the friction and wear characteristics of two representative compounds, (1) 3-tri-n-butylstannyl (diphenyl) and (2) 3-tri-n-butylsilyl (diphenyl). Friction and wear test conditions included a 1-kg load, 25 to 225 C disk temperatures, and a dry air atmosphere. The tin and silicon compounds yielded friction and wear results either lower than or similar to those obtained with a polyphenyl ether and a C-ether. The maximum thermal decomposition temperatures obtained in the silicon and tin series were 358 and 297 C, respectively. Increasing the steric hindrance around the silicon or tin atoms increased the thermal stability. Future work with these compounds will emphasize their use as antiwear additives rather than base fluids.

Jones, W. R., Jr.↗
NASA NTRS1973

The effect of oxygen concentration on the boundary lubricating characteristics of an unformulated C-ether to 300 C

The effect of oxygen concentration on the boundary lubricating characteristics of an unformulated C-ether was studied with the use of a ball-on disk sliding-friction apparatus. Results were compared with those obtained with a polyphenyl ether. Experimental conditions included oxygen concentrations ranging from 20 percent (air) to 0.001 percent (nitrogen), a load of 1 kilogram, a sliding speed of 17 meters per minute, and disk temperatures ranging from 20 to 300 C (77 to 572 F). The C-ether yielded better boundary lubricating characteristics than did the polyphenyl ether in air and nitrogen over most of the temperature range. The C-ether exhibited lower wear at high oxygen levels (10 to 20 percent O2) from 25 to 200 C (77 to 392 F) and at low oxygen levels (0.001 to 1.0 percent O2) from 200 to 300 C (392 to 572 F). Friction polymer was observed around the wear scars of most test specimens. Friction polymer generation and its effect on wear are discussed in light of current theories.

Jones, W. R., Jr.↗
NASA NTRS1972

Boundary lubrication of formulated C-ether in air to 300 deg C. 1: Phosphorus ester additives

Friction and wear measurements were made on CVM M-50 steel lubricated with three C-ether (modified polyphenyl ether) formulations in dry and wet air. Results were compared to those obtained with a formulated Type 2 ester and the C-ether base fluid. A ball-on-disk sliding friction apparatus was used. Experimental conditions were a 1-kilogram load, a 17-meter-perminute (100-rpm) surface speed, and a 25 to 300 C (77 to 572 F) disk temperature range. The C-ether base fluid and the three formulated C-ether fluids yielded lower wear than the Type 2 ester over the entire temperature range. All C-ether fluids exhibited slightly higher friction coefficients than the ester from 150 to 300 C (302 to 572 F) and similar values from 25 to 150 C (77 to 302 F). In general, lower wear rates were observed with the C-ethers when tested in wet air as compared to a dry air atmosphere.

Jones, W. R., Jr.↗