ISO/TC 123/SC 2 - Materials and lubricants, their properties, characteristics, test methods and testing conditions

This document specifies parameters for the hardness testing of solid materials for plain bearings made from cast and wrought copper and aluminium alloys by machining and forming, of their wrought products and ingots, and of tin-based ingots. This document is a supplement to existing International Standards on hardness testing and, therefore, includes only the extensions and restrictions for observation compared to those publications. Owing to the heterogeneous structural composition of the majority of these bearing metals, a Brinell test is used.

This document specifies а method for the determination of the endurance limit in fatigue of bearing materials alone (not attached to steel backing).

This document specifies requirements for cast copper alloys for use in solid and multilayer thick-walled plain bearings. It gives a limited selection of alloys currently available for general purposes.

This document specifies requirements for wrought copper alloys for use in solid plain bearings, particularly for bushes. This document provides a limited selection of alloys currently available for general purposes.

This document specifies a classification and designation system for a selection of the most common unfilled thermoplastic polymers for plain bearings. The unfilled thermoplastic polymers are classified on the basis of appropriate levels of distinctive properties, additives and information about their application for plain bearings. The designation system does not include all properties; thermoplastic polymers having the same designation cannot therefore be interchanged in all cases. It also provides an outline of the properties and applications of the most common unfilled thermoplastic polymers as well as listing some of the fundamental parameters that influence the selection of thermoplastic polymers for use for plain bearings. NOTE In the further course of the work, it is intended to prepare standards on “thermosetting polymers” and “mixed polymers” for plain bearings.

This document specifies a method of improving test result comparability by evaluating the stresses in the bearing layers leading to fatigue (see Annex A). A similar evaluation is required in practical applications. Because the stresses are the result of pressure build-up in the hydrodynamic film, it is essential to fully state the conditions of operation and lubrication. In addition to dynamic loading, dimensional and running characteristics, the inclusion of the following adequately defines the fatigue system: a) under conditions of dynamic loading the minimum bearing oil film thickness as a function of time and location to ensure no excessive local overheating or shearing as a result of mixed lubrication when running in; b) the distribution of pressure circumferentially and axially with time under dynamic loading; c) from this the resulting stresses in the bearing layers as a function of time and location, especially the maximum alternating stress. Furthermore, bearing fatigue can be affected by mixed lubrication, wear, dirt, tribochemical reactions and other effects encountered in use thus complicating the fatigue problem. This document is therefore restricted to fatigue under full hydrodynamic separation of the bearing surfaces by a lubricant film. This document applies to oil-lubricated plain cylindrical bearings, in test rigs and application running in conditions of full hydrodynamic lubrication. It comprises dynamic loading in bi-metal and multilayer bearings. NOTE The number of practical applications with different requirements has led to the development of many bearing test rigs. If the conditions of lubrication employed on these test rigs are not defined in detail, test results from different rigs are generally neither comparable nor applicable in practice. Different test rigs can yield inconsistent ranking among equal materials.

This document specifies the requirements for an engine bearing test rig that uses an actual connecting rod to determine plain bearing performance in automotive engines, evaluating fundamental bearing properties such as seizure resistance, wear resistance, fatigue resistance and resistance to the impact of foreign material.

This document defines requirements for the testing of lubricated plain journal bearings in test rigs, running under conditions of hydrodynamic or mixed lubrication, during bearing and/or material development. It deals with both static and dynamic loading in solid and multi-layer journal bearings. It is not applicable to the testing of dynamic characteristics of lubricant film in journal bearings applied in calculation of vibration and stability of turbo-rotors. NOTE It is intended that further details of test procedures be established when carrying out testing based on this document.

This document defines, describes and classifies the characteristics of damage occurring in service to hydrodynamically lubricated metallic plain bearings and journals. It assists in the understanding of the various characteristic forms of damage which can occur. Consideration is restricted to damage characteristics which have a well-defined appearance and which can be attributed to particular damage causes with a high degree of certainty. Various appearances are illustrated with photographs and diagrams.

This document defines, describes and classifies the characteristics of damage occurring in service in hydrodynamically lubricated metallic plain bearings due to cavitation erosion, together with possible countermeasures. It assists in understanding the various characteristic forms of damage which can occur. Consideration is restricted to damage which has a well-defined appearance and which can be attributed to particular causes with a high degree of certainty. Various appearances are illustrated with photographs and diagrams.

This document specifies an ultrasonic testing method for determining bond defects between the bearing metal and the backing. The test can be performed on metallic multilayer plain bearings consisting of steel- or copper-based material backings lined with bearing metal based on lead and tin, with layer thicknesses greater than or equal to 0,5 mm. For cast iron backings, this document is applicable with restrictions. The ultrasonic signal reflected by the bond interface between the bearing metal and the backing is used to determine bonding defects. Ultrasonic testing is not possible on edge zones of sliding surface, flange sides, joint areas, oil holes, grooves, etc. in a range of less than half the diameter of the ultrasonic probe because of undefined reflections. The same applies to bearings with dovetail keying grooves at the bond. Ultrasonic testing of bond does not apply along the edges of the dovetails. Evaluation of the bond on the visible transition from the backing to the bearing metal (on end faces or joint faces) is only practicable by the penetrant testing method specified in ISO 4386-3. This document only describes in detail the pulse-echo method. Within the meaning of this document, the ultrasonic method only permits a qualitative evaluation of the bonding and not a quantitative determination of the bond strength. The ultrasonic bond test differs only between bond and bond defect.

This document specifies a tensile test method for determination of the bond strength between the bearing metal and the backing. The test can be applied to multilayer plain bearings with bearing metals based on lead, tin, copper or aluminium. For tested layer thicknesses ≥ 2 mm, a raw lining thickness of a minimum additional 1 mm is necessary. The backings are from steel, cast steel or copper alloys. The bond strength test does not apply to bearings with cast iron backing. The test applies to all thrust bearings and to journal bearings with an inner diameter of backing ≥ 90 mm. The test can be used for comparative investigations into the influence on the bond strength of various processes and types of material. In addition, the test is suitable for production control and for process qualification of bearing production. For non-destructive ultrasonic testing of the bond between bearing metal and backing for bearing metal layer thicknesses ≥ 2 mm, see ISO 4386-1.

This document specifies a method for the determination of the endurance limit in fatigue of plain strips of multilayer bearing materials. Additionally, it provides the opportunity of studying the influence on the strips of hydraulic pressure and variable temperature.

This document specifies parameters for the hardness testing of compound materials for plain bearings made from steel and bearing metal with bearing metals based on copper and aluminium, manufactured by casting, sintering or bonding. It represents a supplement to the existing ISO publications on hardness testing and, therefore, includes only the extensions and restrictions to be observed compared to those publications. The measuring method applied depends on the bearing metal layer thickness, its hardness and its structure.

This document specifies a non‑destructive penetrant testing for determining bond defects and discontinuities in the sliding surface of the bearing. The penetration method is used to detect a) bond defects in the transitional area between the bearing backing/bearing material on the end faces and joint faces of multilayer plain bearings which cannot be detected by the ultrasonic testing method specified in ISO 4386‑1, and b) discontinuities in the sliding surface of the bearing. The penetration method is applicable, in principle, to finished multilayer plain bearings. The bond test is usually carried out on cast multilayer plain bearings, with a backing consisting of steel, cast steel or cast bronze. It can also be used as a non-production method to aid detection of manufacturing process defects with other bearing material types. Bearing backings which cannot be tin-plated, or only with difficulty, such as perlitic cast iron, rust-resistant steel and cast aluminium, cannot be tested since no bond is possible between the bearing material and bearing backing.

This document gives requirements and guidance to obtain the optimum bond between backing and bearing metal for thick-walled multilayer plain bearings. This optimum bond depends on the chemical composition, the state of stress, the structural arrangement and the machining of the bond surface of the backings. NOTE Control of the manufacturing process is an important requirement to achieve an optimum bond between backing material and bearing metal.

This document specifies a method of determining the σ0,01*‑limit for the steel backing of thin‑walled multilayer half bearings for bearing diameters up to 80 mm. It can also be used for bearing diameters up to 160 mm.

ISO 10129:2017 establishes a test of the corrosion-resistance of bearing materials to lubricants. It also specifies the most important general principles for carrying out such corrosion testing.

ISO 6279:2017 specifies the composition and properties of preferred cast aluminium alloys for use in solid plain bearings. Other alloys can be specified with agreement between the manufacturer and user.

ISO 4383:2012 specifies requirements for multilayer materials for the manufacture of thin-walled plain bearings (half bearings, bushes, thrust washers).

This part of ISO 7148 specifies tribological tests of polymer-based plain bearing materials under specified working conditions, i.e. load, sliding velocity and temperature, with and without lubrication. From the test results, data are obtained which indicate the relative tribological behaviour of metal-polymer and polymer-polymer rubbing parts. The purpose of this part of ISO 7148 is to obtain, for polymer material combinations used in plain bearings, reproducible measured values for friction and wear under specified and exactly-defined test conditions without lubrication (dry surfaces) and with lubrication (boundary lubrication). The test results give useful information for practical application only if all parameters of influence are identical. The more the test conditions deviate from the actual application, the greater the uncertainty of the applicability of the results.

1 Scope This part of ISO 7148 specifies tribological tests of metallic bearing materials for plain bearings under conditions of boundary lubrication. The test procedures described in this part of ISO 7148 enable the friction and wear behaviour of bearing material/mating/lubricant combinations to be compared with that of other combinations, thus facilitating the selection of a bearing material for running repeatedly or for long periods under conditions of boundary lubrication, low speed and continuous sliding. Owing to differences in test conditions, measured friction and wear values can be expected to vary from one test facility to another. The test results give useful information for practical application only if all parameters of influence are identical. The more the test conditions deviate from the actual application, the greater the uncertainty of the applicability of the results.

ISO 4381:2011 specifies requirements for bearing metals based on tin casting alloys for multilayer plain bearings. The chemical composition and material properties refer to the original unprocessed material and are measured on representative samples. Testing results on final bearings can differ due to the influence of bearing production. Therefore, it is not intended that these results be compared with data given in ISO 4381:2011.

Specifies a method for the determination of the endurance limit in fatigue of half-bearings of multilayer bearing materials. The principle of the method is clamping the specimens at one end and loading them at the other end by force or displacement applied radially. The load shall fluctuate from tension to compression.

This compression testing serves for the determination of the behaviour of metallic materials under uniaxial compression loading which ist uniformly distributed over the cross-section. For this purpose, a cylindrical specimen is subjected to compression which is slowly and continuously increased, and the compressive force used is measured.

ISO 4386-1:2012 specifies an ultrasonic testing method for determining bond defects between the bearing metal and the backing. The test can be performed on metallic multilayer plain bearings consisting of steel- or copper-based material backings lined with bearing metal based on lead and tin, with layer thicknesses greater than or equal to 0,5 mm. For cast iron backings, ISO 4386-1:2012 is applicable with restrictions.

ISO 4386-2:2012 specifies a tensile test method for determination of the bond strength between the bearing metal and the backing. The test can be applied to multilayer plain bearings with bearing metals based on lead, tin, copper or aluminium. For tested layer thicknesses of greater than or equal to 2 mm, a raw lining thickness of a minimum additional 1 mm is necessary. The backings are from steel, cast steel or copper alloys. The bond strength test does not apply to bearings with cast iron backing. The test applies to all thrust bearings and to journal bearings with an inner diameter of backing of greater than or equal to 90 mm. The test can be used for comparative investigations into the influence on the bond strength of various processes and types of material.

ISO 4384-1:2012 specifies parameters for the hardness testing of compound materials for plain bearings made from steel and bearing metal with bearing metals based on copper and aluminium, manufactured by casting, sintering or bonding. It represents a supplement to the existing ISO publications on hardness testing and, therefore, includes only the extensions and restrictions to be observed compared to those publications.

ISO 4384-2:2011 specifies parameters for the hardness testing of solid materials for plain bearings made from cast and wrought copper and aluminium alloys by machining and forming their wrought products and ingots, and of tin-based ingots. It represents a supplement to existing International Standards on hardness testing and, therefore, includes only the extensions and restrictions for observation compared to those publications.

ISO 7146-2:2008 defines, describes and classifies the characteristics of damage occurring in service in hydrodynamically lubricated metallic plain bearings due to cavitation erosion, together with possible countermeasures. It assists in understanding the various characteristic forms of damage which may occur. Consideration is restricted to damage which has a well-defined appearance and which can be attributed to particular causes with a high degree of certainty. Various appearances are illustrated with photographs and diagrams.

ISO 7146-1:2008 defines, describes and classifies the characteristics of damage occurring in service to hydrodynamically lubricated metallic plain bearings and journals. It assists in the understanding of the various characteristics of damage which may occur. Consideration is restricted to damage characteristics which have a well-defined appearance and which can be attributed to particular damage causes with a high degree of certainty. Various appearances are illustrated with photographs and diagrams.

ISO 6281:2007 establishes guidelines for the testing of lubricated plain journal bearings in test rigs, running under conditions of hydrodynamic or mixed lubrication, during bearing and/or material development. It deals with both static and dynamic loading in solid and multi‑layer journal bearings.

ISO 6279:2006 specifies the composition and properties of preferred cast aluminium alloys for use in solid plain bearings.

ISO 10129:2006 establishes a test of the corrosion-resistance of bearing materials to lubricants. It also gives the most important general principles for carrying out such corrosion testing.

This International Standard specifies a classification and designation system for a selection of the most common unfilled thermoplastic polymers for plain bearings. The unfilled thermoplastic polymers are classified on the basis of appropriate levels of distinctive properties, additives and information about their application for plain bearings. The designation system does not include all properties; thermoplastic polymers having the same designation cannot therefore be interchanged in all cases. It also provides an outline of the properties and applications of the most common unfilled thermoplastic polymers as well as listing some of the fundamental parameters that influence the selection of thermoplastic polymers for use for plain bearings. NOTE In the further course of the work it is intended to prepare standards on "thermosetting polymers" and "mixed polymers" for plain bearings.

Describes a method of improving test result comparability by evaluating the stresses in the bearing layers leading to fatigue. A similar evaluation is required in practical applications. Because the stresses are the result of pressure build-up in the hydrodynamic film, it is essential to fully state the conditions of operation and lubrication. Is restricted to fatigue under full hydrodynamic separation of the bearing surfaces by a lubricant film.

Specifies a method for the determination of the endurance limit in fatigue of multilayer bearing materials alone (not attached to steel backing). The test specimens are described in detail, the method specified is based on carrying out a number of stress cycles (ultimate number is 5 × 10^7 cycles), the fatigue strength for finite life shall be recorded commencing at 10^7 cycles.

Specifies a method for the determination of the endurance limit in fatigue of plain strips of multilayer bearing materials. Additionally, the method provides the opportunity of studying the influence on the strips of hydraulic pressure and variable temperature.

Specifies in detail a corrosion test under conditions of static load, i.e. without any mechanical action taking place simultaneously. In order for corrosion tests to be evaluated and compared, it is necessary to carry them out in accordance with the conditions laid down in this report.

Defines, describes and classifies the characteristics and causes of damage and changes in appearance occurring in service in hydrodynamically lubricated plain bearings and journals. Consideration is restricted to characteristic forms of change and damage which have a well-defined appearance and which can be attributed to particular causes with a high degree of certainty. The features peculiar to the change and damage are described, the various forms are illustrated with photographs and diagrams, and the most frequent causes are given.

Specifies a testing method for determining bond defects between the bearing metal and the backing. Describes in detail only the pulse-echo method in which the probe is applied from the bearing metal side.

Describes safety precautions, preparation of test surface, application of penetrant, removal of excess penetrant, application of the developer, inspection, subsequent cleaning and the test report.