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Fiber Optic Strain Sensor Standardization - International and European Activities

There are worldwide activities in developing guidelines and standards for fiber optic sensors. Fiber optic sensors (FOS) are increasingly demanded for structural health monitoring purposes and for measurement of physical and chemical quantities because of their specific features. However, they are not yet widely established for practical use due to a lack of guidelines and confirmed standards. Therefore, there are few groups worldwide which are very active in developing standards for use of FOS in different fields, particularly driven from aircraft industry, oil industry or the necessity to provide sensor systems for health monitoring of structures with a certain level of risk. The benefits of guidelines and/or standards on the way to well-validated and well-specified sensor systems will be presented by means of related examples. The presentation will also give an overview on the state-of-the-art and most relevant activities. Results achieved are discussed.

Study of Materials and Coatings Used for Drilling Carbon Fiber Re-inforced Plastics

With the increased usage of Carbon Fiber Reinforced Plastics (CFRP) in the aircraft industry, there has been increased pressure to improve cutting tool life. Tungsten carbide tools were the first to be applied to CFRP materials. Poly Crystalline Diamond (PCD) tools also became an acceptable material to be used as a cutting tool material. In recent years, Chemical Vapor Deposition (CVD) diamond tools have become more popular as a cutting tool material for CFRP. This study compares these possible cutting tool materials in the drilling of CFRP. Wear is measured as well as hole quality. Life is determined by common industry standards with regard to fiber break out in a common CFRP material. An economic analysis is conducted in order to determine cost per hole. Presenter Christophe Petit

Ionic Liquids as Novel Lubricants or Lubricant Additives

For internal combustion engines and industrial machinery, it is well recognized that the most cost-effective way of reducing energy consumption and extending service life is through lubricant development. This presentation summarizes our recent R&D achievements on developing a new class of candidate lubricants or oil additives ionic liquids (ILs). Features of ILs making them attractive for lubrication include high thermal stability, low vapor pressure, non-flammability, and intrinsic high polarity. When used as neat lubricants, selected ILs demonstrated lower friction under elastohydrodynamic lubrication and less wear at boundary lubrication benchmarked against fully-formulated engine oils in our bench tests. More encouragingly, a group of non-corrosive, oil-miscible ILs has recently been developed and demonstrated multiple additive functionalities including anti-wear and friction modifier when blended into hydrocarbon base oils.
Technical Paper

Data on Machinability and Wear of Cast Iron

THE hardness or chemical composition of an iron is, by itself, no indication of the wearing property and machinability of the iron. Irons containing a large amount of free ferrite have been found to wear rapidly, whereas others having considerable pearlite or sorbite in their structure show good wearing properties. The presence in cylinder-blocks of excess-carbide spots or of phosphides of high phosphorus-content is deleterious, because such spots wear in relief and the material ultimately breaks out, acting as an abrasive that scores the surfaces. Causes of wear in cylinder-blocks are discussed, and nickel, or nickel and chromium, intelligently added to the iron is suggested as a means of obtaining the correct microstructure for a combination of good wearing properties and machinability.
Technical Paper

Correlating Test-Data on Heat-Treated Chromium-Vanadium Steels

AN outline is given of the work performed and the method of procedure followed in correlating test results on specimens of heat-treated S.A.E. chromium-vanadium steel 6130 as a basis for revision of the physical-property charts for certain automotive steels. Revision of the charts was proposed by the Iron and Steel Division of the Standards Committee of the Society, and a subcommittee, of which the author is a member, was appointed to carry on the preliminary work of revision. The paper is a report of the results of the tests made. Test specimens of S.A.E. Steel 6130, to be drawn at three different temperatures after quenching, were prepared by four steel manufacturers. These were distributed among 30 cooperating laboratories, which made a series of about 115 tests including complete chemical analysis, tensile-strength, and Brinell, scleroscope and Rockwell hardness tests on the specimens.
Technical Paper

Modern Light Alloys and Their Application to Aircraft-Engine Design

A NUMBER of the more important commercial alloys having aluminum as their base are discussed by the author, who points out their main physical characteristics and outlines methods which can be used in their fabrication, indicating in a general way which alloys are best suited to various aircraft-engine requirements. Tables are given showing chemical compositions and physical properties, including a table of physical properties of various casting alloys at elevated temperatures. Special-purpose alloys are commented upon, and also a new aluminum alloy for pistons which is beginning to find commercial application and possesses properties particularly desirable in aircraft engines. Recent developments in magnesium alloys and their application to aircraft-engine design are specified, tables of physical properties are given, and comments are made on the characteristics of the material as compared with aluminum alloys.
Technical Paper

Bearing Bronzes with Additions of Zinc, Phosphorus, Nickel and Antimony

SEVEN basic copper-tin-lead bearing-bronzes having high copper contents were studied by the application of various mechanical tests, such as Brinell hardness, resistance to impact, resistance to repeated pounding and resistance to wear. The effects of various additions were investigated by preparing test bearings of the same base alloys with additions of zinc, phosphorus, nickel and antimony, taken singly, and applying the same tests to these. The preparation of the test castings and the methods of testing are described in detail. The chemical analyses are given for the 40 different alloys tested; and the results of the various tests on each group of alloys are reported and discussed in detail, with the observations charted and tabulated for convenient reference. A tabulation of the specifications of 54 different bearing bronzes now in use is included in the paper. Dr. Dowdell presented and discussed∗ the paper for the authors.
Technical Paper

Ignition Quality of Diesel Fuels as Expressed in Cetene Numbers

THE paper is an account of some further experiences and views on the subject of ignition in oil engines, which, with the advent of the high-speed Diesel engine, has received much attention of late. The Delft Engine Laboratory of the Royal Dutch Shell Group has been working on oil-engine fuels for nearly four years, with the aid and assistance of all the group's chemical and physical specialists. It had already been working on ignition problems before the high-speed engine was introduced, these problems belonging to a continuous series. Though ignition problems have become of paramount importance in present-day high-speed engines, they have always played a certain rôle with certain fuels also in low-speed engines which were not sufficiently recognized.
Technical Paper


Annual Meeting and Detroit Section Paper - As the success or failure of the finish of an automobile depends largely on the finishing-varnish, a plea is made for more scientific analyses of the problems of automobile finishing and more care in selecting and applying a suitable varnish. The qualities to be desired in a finishing-varnish are divided into two classes: the shop qualities and the service qualities. The shop qualities include color, body or viscosity, working, flowing, setting, hardening, fullness and the safety of working. The service qualities, or those that enable the varnish to withstand the various conditions of use, include resistance to break-down under the chemical action of the actinic rays of sunlight, to the destructive action of moisture and the alkalis in mud and soap, to expansion and contraction, to vibration and to abrasion.
Technical Paper


In a study of the dust problem that has lasted more than 2 years, many observations, measurements and experiments were made to determine the nature and effect of dust and the best means for its elimination as a cause of engine wear. The results of these experiments, which seem to be of general interest, are reported and cover briefly such matters as the chemical composition of road dust, its particle size, specific gravity, and abrasive nature and the relative amounts of it to which an engine may be exposed under varied conditions. Curves are also submitted that show the average cylinder-wear on a number of test cars. The methods of testing air-cleaners are described, the principles underlying commercial air-cleaners are discussed and a list of what the author believes to be important elements of air-cleaners for passenger cars is given.
Technical Paper


Following a description of airplane structure, the author discusses structural requirements and outlines the main features of properly coordinating the engineering and the manufacturing activities. He says that each of the three subdivisions of airplane design has its own series of calculations, these being related to predictions of performance before the machine is built, to stability determinations and to the design of a self-contained structure of sufficient strength to withstand any stresses developed in flight or in landing. He states also that no inspection is worth the name or the money spent on it that does not include constructive work and a knowledge at all times that the intentions of the designers are being carried out in detail so that the safety of the craft is assured. Materials used in aircraft should be light and easily workable and should possess the desired physical and chemical properties; they must have the specified cross-section and be free from defects.
Technical Paper

Cast Iron in Its Relation to the Automotive Industry

CAST iron is purchased on a basis of price instead of quality, according to the author, who says that this has depreciated the qualities of the material generally and caused engineers to look askance at its application. Combined with such factors is the influence of misinformation about cast iron that has been widely broadcast. Questions regarding the design of patterns and cheaper raw-materials have involved the foundrymen in controversial discussion concerning the influence of various elements to the detriment of the economic condition of the iron industry as well as that of the consumer of castings. Due to the lessening of the consumption of cast iron, the foundry world has inaugurated research to better the quality of cast iron, not only through investigations of raw materials but also by improvement in melting practice.
Technical Paper


Stating that the production of satisfactory gears is one of the most serious problems confronting the automobile builder, the authors give an outline of the practice of producing gears that is used by the company they represent and describe a new method for cutting the rear-axle drive-pinion by using two machines, each machine cutting one side of the teeth. Explanations are given of the various steps in the process and the reasons for stating that this method is not only cheaper but produces gears of higher quality. Numerous suggestions are made for improving gears and axles, and the claim is made that it is doubtful if the spiral-bevel gear has had a fair chance because axles usually have not been designed so that the main consideration was the requirements of the gears.
Technical Paper


The author first points out how increasing population and rising standards of living have increased the demand for foodstuffs and how such industrial activities as are brought about by the present conflict magnify the seriousness of the food problem, not only by withdrawing workers from the farms, but also by increasing food consumption on the part of those engaged in the speeded-up industries in order to supply the increased human energy required. The author then passes to a discussion of the tractor as a means for increasing the food supply by taking the place of withdrawn labor and cheapening production. Several charts show the effect of increased individual activity on food consumption, the relation of food consumption to standards of living and the growth of population, the variation of food demand during political activities during the past century, and the relation of the cost per calorie of various cereals.
Technical Paper

A Post War View of Alloy Steels

The development of NE steels was facilitated by the previous work on the standardization of hardenability testing and on the calculation of hardenability from chemical composition and grain size. The importance of susceptibility to brittle failure has been emphasized by war experiences. Stress concentrations, low temperatures and high loading rates contribute to brittle failures. Temper brittleness, a potential cause of brittle failures, requires the determination of impact strength at a number of temperatures rather than just at room temperature. The best combinations of strength and toughness are generally found in steel which has been tempered after having been hardened to a fully martensitic structure. If present, the nature and distribution of the non-martensitic constituents are important.
Technical Paper


THE application of high strength adhesives to the fabrication of automotive parts and assemblies is discussed here by Mr. Swayze, who covers the design, tooling, and inspection phases of the subject, the properties of adhesives, and the relative cost of chemical bonding, compared with other methods of assembly. To benefit fully from the use of adhesives, the author reports that the parts must be designed so that loads applied to the bond are in shear or direct tension, eliminating peel and cleavage. Freedom of design, he added, however, is permitted by the wide variety of materials that can be bonded in all sorts of combinations.
Technical Paper

Effect of Fuel Properties on Diesel - Engine Performance

THE studies discussed here suggest that the power developed in a diesel is directly proportional to the heating value of the fuel and is independent of its cetane rating, volatility, chemical composition, and molecular structure. Both cetane and volatility, however, the authors say, have marked effects upon cold starting and light-load operation, when the ignition capacity of the cylinder is reduced.
Technical Paper


THE present state of the art regarding the formulation of automotive and aviation lubricants from the standpoint of protecting metal parts against mechanical and chemicalwear is outlined in this paper. The discussion is limited to four classes of lubricants, namely, (a) engine oils, (b) transmission oils, (c) rear-axle oils, and (d) greases. By virtue of the wide variety of service conditions to which they are subjected, engine parts can be worn as the result of either mechanical or chemical action. Engine oils must be designed, therefore, to cope with both these types of wear. Oil viscosity and viscosity index are both important factors in engine wear. Various types of additives are being used to an increasing degree as “alloying” materials in engine oils to control their wear characteristics. A trend toward the use of specially synthesixed lubricants for both aviation and automotive service is in evidence.
Technical Paper

Some Factors Affecting Precombustion Reactions in Engines

USE of a motored engine as a convenient method for studying precombution reactions is described in this paper. Preliminary investigations of this technique were made in 1950, and this paper covers the work accomplished since then in establishing a better understanding of chemical reactions preceding knock. Extent and type of precombustion reactions which occur in the unburned charge ahead of the flame front determine the tendency of a fuel-air mixture to knock. Use of a motored engine substitutes compression of the unburned charge by the piston for compression of the end gas by the flame front. The buildup of knock-producing materials is considered in studies of mixture compositions and time factors. Observed precombustion reactions are related to problems concerning the adaptation of fuels to engines.
Technical Paper

Combustion-Chamber Deposition and Knock

THIS paper discusses a number of factors involved in the problem of octane-number requirement increase due to combustion-chamber deposits. A laboratory single-cylinder engine test procedure, which evaluates the effects of various fuel and oil factors, is presented with data showing its correlation with passenger-car operation under light-duty, city-driving conditions. The influence of engine operating conditions during accumulation of deposits and the importance of engine conditions selected to evaluate the magnitude of the requirement increase are illustrated. It is indicated that organic materials formed from both fuel and oil are of major importance in deposit formation. Data are presented which show that tel added to pure hydrocarbons of different chemical types may have different effects. It is shown that the carbon/hydrogen ratio of leaded pure hydrocarbons influences the amount and composition of the deposit formed.