摘要:

The method of predicting seal swell previously reported by this laboratory, has been extended to include three-dimensional solubility parameter concepts. Techniques for analysis and the calculation of the partial solubility parameters in consistent dimensions have been formulated for pure liquids, binary mixtures of known composition, and multicomponent mixtures of unknown ingredients.

ISSN:0569-8197    

DOI:10.1080/05698196908972241

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Low-speed friction tests with fine diamond styli and spherical sliders of ruby, sapphire, and hardened steel were carried out on the crystallographically prominent planes of synthetic single-crystal rutile at room temperature. The friction against diamond was 0.04–0.10; against sapphire and steel, 0.10–0.15. Ploughing friction was found to be anisotropic. When larger sliders were used so that the contribution by ploughing was minimized, the frictional anisotropy vanished. The anisotropy of ploughing was correlated with plastic deformation by slip in and adjacent to the friction track, as seen and studied with the optical microscope. Surface damage by cleavage and brittle failure was found to be severe during the friction experiments.Presented as an American Society of Lubrication Engineers paper of the ASME/ASLE Lubrication Conference held in Atlantic City, New Jersey, October 8–10, 1968.

ISSN:0569-8197    

DOI:10.1080/05698196908972242

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

ISSN:0569-8197    

DOI:10.1080/05698196908972243

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Physical d-c sputtering of MoS2was used to apply MoS2films for as a solid lubricant on rotating and sliding components. This method does not utilize binders or burnishing. Friction experiments in vacuum (10−11torr) were conducted on these films (approx. 2000 Å thick). The coefficient of friction for these films were similar to the reported values for resin bonded films 0.03–0.08. The long endurance life of these films in friction experiments indicates good adherence. The good adherence results from cleanliness of the surface (etched) and the relatively high energies of the sputtered material on arrival at the surface. These sputtered MoS2films were consistent in regard to stoichiometry, adherence, thickness, and uniformity when the sputtering conditions were accurately controlled from run to run.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference held in Atlantic City. New Jersey, October 8–10, 1968.1Some of this information has been published as NASA TN D-4269.

ISSN:0569-8197    

DOI:10.1080/05698196908972244

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The friction properties of two groups of copper-based bearing alloys, one with nominal compositions of 6% Sn, and 0, 5, 10, 15, 20, 25% Pb, and the other with 15% Pb and 0, 3, 6, 9, 12 and 15% Sn, were studied in argon and air as well as in various lubricants of 25 ± 1 C. Without lubrication, the presence of lead is essential in that the smeared Pb film, which is formed on the bronze surface by extrusion from the matrix, protects the steel shaft from severe damage. Up to 10%, Pb also lowers the wear of the bearing material itself appreciably. Up to 9%, Sn is beneficial. When a relatively viscous lubricant is applied, a running-in period is followed by a transition towards a fully hydrodynamic condition (f < 0.01). A “critical load” (Lc) exists, below which running-in wear is negligible and above which excessive wear occurs. Under these conditions, alloys with a coarse Pb distribution behave much better than alloys with finely divided Pb. In fine-grained alloys, addition of Pb is unfavorable as Pb lowers the value of Lc, drastically. Also, this effect is explained in terms of a lubricant adsorption mechanism in which are taken into account the lubricant adsorbing function of tin and the heat conductivity of the alloys.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference held in Atlantic City, Now Jersey, October 8–10, 1968.

ISSN:0569-8197    

DOI:10.1080/05698196908972245

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The development of a liquid-phase micro panel coker and a vapor-phase micro panel coker is described. The devices are intended primarily for use in screening synthetic lubricants on the basis of deposit formation in instances where only research-size sample quantities are available. Each model requires less than 75 ml of sample per test and is capable of operation to 1000 F panel temperature. Both micro coker models were utilized in an experimental investigation of the effects of lubricants, panel temperature, and dry and moist air on lubricant deposition. In addition, the liquid-phase micro coker data are examined in comparison with full-scale panel coker and bearing deposition test results.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference held in Atlantic City, New Jersey, October 8–10, 1968.

ISSN:0569-8197    

DOI:10.1080/05698196908972246

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Experiments and analyses were performed to determine the cooling requirements for 40-millimeter bore bearings using 60 R (-400 F) hydrogen gas. The bearings were run at shaft speeds to 35,000 rpm and thrust loads to 400 lb. A bronze-filled Polytetrafluoroethylene (PTFE) retainer was used to lubricate the bearings.

ISSN:0569-8197    

DOI:10.1080/05698196908972247

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

A method was described to normalize wear-induced changes in the dynamic friction of surfaces lubricated with an additive in oil solution. Changing dynamic friction data were normalized by comparing them at equivalent degrees of boundary lubrication, determined by measuring the coefficient of friction of the surfaces in neat white oil. Friction tests were made with three different additives to demonstrate the method and its validity.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference held in Atlantic City, New Jersey, October 8–10, 1968.

ISSN:0569-8197    

DOI:10.1080/05698196908972248

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The extreme pressure properties of fluorides and silicofluorides as lubricants for titanium were studied using the Falex tester. With water solution of sodium fluoride and water soluble metallic and nonmetallic silica-fluorides, jaw loads of 1500 lb were attained without welding. Use of ceramic blocks in the Falex tester showed the efficacy of the fluorides and silicofluorides in preventing excessive metal build up on the ceramic blocks, or excessive wearing away of the ceramic blocks. Sodium fluoride was superior to potassium or ammonium fluoride, and ammonium silicofluoride was the best of the silicofluorides when combined with sodium fluoride.

ISSN:0569-8197    

DOI:10.1080/05698196908972249

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The spark shower that is commonly observed when ferrous metals and other alloys are abraded is caused by the exothermic reaction of atmospheric oxygen with the freshly formed surfaces of the metal chips. This reaction greatly facilitates grinding as evidenced by a large increase in grinding forces when oxygen is removed from the tool-metal interface. Examination of grinding swarf combined with calculations of the kinetics of the oxidation reaction indicate that oxidation leads to increased plasticity of the metal during chip formation.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference held in Atlantic City, New Jersey, October 8–10, 1968.

ISSN:0569-8197    

DOI:10.1080/05698196908972250

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor