{"title":"Grease Lubrication: Formulation Effects on Tribological Performance","authors":"T. Cousseau","doi":"10.5772/intechopen.101549","DOIUrl":"https://doi.org/10.5772/intechopen.101549","url":null,"abstract":"Grease lubrication performance prediction is challenging. Only recently that empirical equations to predict grease film thickness for prevailing rolling conditions under fully flooded lubrication taking into account thickener properties and content for low, moderate, and high speeds were developed. At starved lubrication, although new insights about the supply and loss mechanisms that govern film formation have been published, contact replenishment and, consequently, film thickness predictions for long-term operation are still not available. Prediction of components efficiency requires film thickness values and properties, including film’s molecular structure, which makes it even more challenging. When it comes to prevailing sliding conditions, the literature is scarce and most of the knowledge developed for prevailing rolling conditions is not applicable. During the sliding of the contacting bodies, boundary and mixed lubrication regimes are expected. In this situation, the tribological response is primarily defined by grease thickener and additives physicochemical interaction with the surface. This complexity leads many researchers to seek simpler relationships between grease formulation and properties with its performance. This review aims to present the state-of-art on grease lubrication and update some of these relationships.","PeriodicalId":269573,"journal":{"name":"Tribology [Working Title]","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127965590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Christian Ortiz Ortiz, E. Hernández‐Rengifo, Julio Cesar Caicedo
{"title":"Analysis of the Tribological Evolution of Nitride-Based Coatings","authors":"Christian Ortiz Ortiz, E. Hernández‐Rengifo, Julio Cesar Caicedo","doi":"10.5772/intechopen.100629","DOIUrl":"https://doi.org/10.5772/intechopen.100629","url":null,"abstract":"This chapter describes the fundamental and technological role of nitride-based hard coatings as protective coatings in some applications within the metalworking industry. For this, this chapter will present a critical review of previous research and recent developments on nitride-based coatings in different systems such as (multilayers, quaternaries, among others), where it will be possible to demonstrate their main properties and advantages that they can grant when they are implemented on conventional steels, such as greater hardness, surface control, electrochemical resistance, resistance against wear, among others. These results will determine that this type of coatings are suitable candidates to be implemented as protective coatings on cutting tools, which suffer from high wear in machining processes in the metalworking industry.","PeriodicalId":269573,"journal":{"name":"Tribology [Working Title]","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116009084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Boidi, Philipp G. Grützmacher, M. Varga, Márcio Rodrigues da Silva, C. Gachot, D. Dini, Francisco J. Profito, Izabel F. Machado
{"title":"Tribological Performance of Random Sinter Pores vs. Deterministic Laser Surface Textures: An Experimental and Machine Learning Approach","authors":"G. Boidi, Philipp G. Grützmacher, M. Varga, Márcio Rodrigues da Silva, C. Gachot, D. Dini, Francisco J. Profito, Izabel F. Machado","doi":"10.5772/intechopen.100245","DOIUrl":"https://doi.org/10.5772/intechopen.100245","url":null,"abstract":"This work critically scrutinizes and compares the tribological performance of randomly distributed surface pores in sintered materials and precisely tailored laser textures produced by different laser surface texturing techniques. The pore distributions and dimensions were modified by changing the sintering parameters, while the topological features of the laser textures were varied by changing the laser sources and structuring parameters. Ball-on-disc tribological experiments were carried out under lubricated combined sliding-rolling conditions. Film thickness was measured in-situ through a specific interferometry technique developed for the study of rough surfaces. Furthermore, a machine learning approach based on the radial basis function method was proposed to predict the frictional behavior of contact interfaces with surface irregularities. The main results show that both sintered and laser textured materials can reduce friction compared to the untextured material under certain operating conditions. Moreover, the machine learning model was shown to predict results with satisfactory accuracy. It was also found that the performance of sintered materials could lead to similar improvements as achieved by textured surfaces, even if surface pores are randomly distributed and not precisely controlled.","PeriodicalId":269573,"journal":{"name":"Tribology [Working Title]","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134256317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tribology in Marine Diesel Engines","authors":"Sung-Ho Hong","doi":"10.5772/intechopen.100547","DOIUrl":"https://doi.org/10.5772/intechopen.100547","url":null,"abstract":"This chapter deals with the tribology of marine diesel engines. Several types of diesel engines have been installed and used in the engine room of marine ships. Some of them, used for propulsion, operate at low-speed in a two-stroke combustion process in conjunction with propellers. Four-stroke engines are used for power generation and operates at medium-speed. In general, two or more four-stroke engines, including spares, are installed in the large ships. Tribological problems are important issue in the respect of reliability in the marine diesel engines, and there are many tribological engine components including bearings, pistons, fuel injection pumps and rollers. Moreover, the marine engines have lubricant problems such as lacquering. Improvements to the tribological performance of marine engine components, and lubricants can provide reduced oil and fuel consumption, improved durability, increased engines power outputs and maintenance. Therefore, this chapter shows better designs and methods in order to improve the tribological problem in the marine diesel engines.","PeriodicalId":269573,"journal":{"name":"Tribology [Working Title]","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122048371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Wear Life of Bonded MoS2 Film Lubricant","authors":"Naofumi Hiraoka","doi":"10.5772/intechopen.99802","DOIUrl":"https://doi.org/10.5772/intechopen.99802","url":null,"abstract":"Bonded MoS2 film lubricants are widely used in industry as solid lubricants. It has excellent lubrication properties, but it also has characteristics that require careful consideration. As is well known, its friction and wear are greatly affected by the environmental atmosphere and its wear life depends on the pre-treatment of the substrate. It was found that in many cases the wear life could not be correctly estimated by a specific wear rate and could be explained by the fatigue life, especially under high loading conditions. The atmosphere dependent wear life can also be explained by the fatigue life.","PeriodicalId":269573,"journal":{"name":"Tribology [Working Title]","volume":"474 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122892781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Remarks on Wear Transitions Related to Hardness and Size of Abrasive Particles","authors":"Giuseppe Pintaude","doi":"10.5772/intechopen.99324","DOIUrl":"https://doi.org/10.5772/intechopen.99324","url":null,"abstract":"Abrasive wear is highly dependent on the characteristics and properties of abrasive particles. Their hardness and size can define the severity of abrasion in terms of wear rates. Typically, critical values have been empirically determined to define the transition between mild and severe wear. This review aims to update some of the issues related to these critical values and their relations to abrasive wear. After presenting the current state-of-art, the following items are discussed: a) the scratchability of materials; b) the particle fragmentation associated with size effects; and c) description of abrasion severity.","PeriodicalId":269573,"journal":{"name":"Tribology [Working Title]","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117227806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}