J. Landa, I. Illarramendi, N. Kelling, M. Woydt, A. Skopp and M. Hartelt
This paper aims to focus on the potential for substituting molybdenum‐based piston ring coatings, which are recognized as “allrounder” by other candidate metallurgies. Another…
Abstract
Purpose
This paper aims to focus on the potential for substituting molybdenum‐based piston ring coatings, which are recognized as “allrounder” by other candidate metallurgies. Another purpose is the tribological interaction of molybdenum‐based and new triboactive/reactive piston ring coatings with low SAP, polymer‐ and metal‐free as well as bionotox engine oils with high‐viscosity indices.
Design/methodology/approach
Substoichiometric titanium dioxide composed of the Magnéli‐types phases Ti4O7 (∼17 per cent), Ti5O9 (∼66 per cent), Ti6O11 (∼17 per cent) deposited by plasma spraying, a vacuum sprayed TiO1,93 and a plasma‐sprayed titanium‐molybdenum carbo‐nitride coated piston rings were compared to a state‐of‐the‐art molybdenum‐based piston ring. They were tribologically characterized by means of BAM and SRV tests lubed under mixed/boundary lubrication by factory fill engine oils, engine oils as blends of hydro‐carbons with esters as well as prototype engine oils based on esters and polyglycols.
Findings
Overall, the molybdenum‐ and titanium‐based ring coatings wore in the same order of magnitude. The ranking depends on the test used. The BAM test favours MKP81A (PL72) more, whereas the SRV methods favour the TinO2n−1 more. The different bionotox and low‐ash prototype engine oils with reduced additive contents displayed isoperformance regarding the tribological behaviour of common and triboreactive materials. They presented no visible weakness in wear resistance, coefficient of friction and extreme pressure properties.
Research limitations/implications
The next steps have to confirm functional properties by different engine and endurance tests.
Practical implications
Titanium‐based piston ring coatings are overall more attractive, as they are primarily refined from titania, which is cheap and not rated at stock exchanges, and they present at least an isoperformance when compared with molybdenum‐based ring coatings.
Originality/value
This supplier report displays the complete methodology in order to substitute molybdenum‐ by titanium‐based piston ring coatings as well as illuminating the beneficial interaction with alternative engine oils in existing engine architectures.
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Michael D. Anestis, Samantha E. Daruwala and Neil Carey
Firearms account for the majority of suicide deaths in the US military and general population. The percentage of suicides resulting from firearms is higher in the military…
Abstract
Purpose
Firearms account for the majority of suicide deaths in the US military and general population. The percentage of suicides resulting from firearms is higher in the military, however, and as such, the ratio of non-lethal to lethal suicide attempts is lower in the military than in the general population. In 2013, Congress passed the National Defense Authorization Act, which facilitated a Department of Defense (DoD) shift toward allowing commanding officers and clinicians to inquire about personal firearms with service members perceived as being at risk and also began giving free cable locks to firearm-owning military personnel. The purpose of this paper is to provide a preliminary understanding of the effectiveness of this change, the authors examined trends in firearm suicide attempts within the US military and general population from 2010 to 2015.
Design/methodology/approach
Data on non-lethal and lethal suicide attempts overall and within specific methods were extracted from the Department of Defense Suicide Event Report and the Centers for Disease Control and Prevention’s Web-based Injury Statistics Query and Reporting System (2011–2015).
Findings
Contrary to expectations, firearms were not utilized in a smaller proportion of suicide attempts within the military post-law change. Consistent with expectations, however, the ratio of non-lethal to lethal suicide attempts increased, particularly after the change in law, with the ratio in the military converging somewhat with that of the general population.
Originality/value
Overall, results were mixed, with only limited and tangential evidence that the change in law has proven effective. More precise data collection will be required in order to fully evaluate such laws.
Jens Kleemann and Mathias Woydt
In a high temperature tribometer, stationary carbon has been tested against different rotating ceramics (SiC, Si3N4, Al2O3, WC‐6Ni, MgO‐ZrO2, (Ti, Mo)(C, N)) and stainless steel…
Abstract
In a high temperature tribometer, stationary carbon has been tested against different rotating ceramics (SiC, Si3N4, Al2O3, WC‐6Ni, MgO‐ZrO2, (Ti, Mo)(C, N)) and stainless steel (DIN 1.4876). The rotating discs were grinded, polished and/or lapped. For most material combinations, the wear morphology is known from available literature. A transfer film with a typical wear pattern was found on the rotating disc. The combination of antimony graphite EK3245 against MgO‐ZrO2 did not form carbonaceous transfer layer. Through advanced variation of the roughness up to Rpk=0.011 μm, the wear rate has been reduced to Kv ≈ 3.5×10−8 mm3/N m at a stable coefficient of friction in a “millirange” of μ∼0.008 for a sliding distance of 20.000 m.
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P. D. Harms, Dina V. Krasikova, Adam J. Vanhove, Mitchel N. Herian and Paul B. Lester
This chapter examines the role of stress and emotional well-being as critical antecedents of important outcomes in the military context. In it, we provide a framework for…
Abstract
This chapter examines the role of stress and emotional well-being as critical antecedents of important outcomes in the military context. In it, we provide a framework for understanding the sources of stress among military personnel. Using this model, we review the risk factors associated with combat and deployment cycles in addition to protective factors, such as personality characteristics and social support, which mitigate the effects of stress on emotional well-being and performance. Finally, we evaluate efforts by military organizations to enhance the emotional well-being of service members through training programs designed to build resiliency.
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A. Mimaroglu, M. Çaliskan and I. Calli
Advanced ceramics such as alumina are widely in use in the design of components for high engineering applications mainly because of their high wear resistance, high compressive…
Abstract
Advanced ceramics such as alumina are widely in use in the design of components for high engineering applications mainly because of their high wear resistance, high compressive strength, low specific density and high temperature capability. Processing and manufacturing of pure alumina products is a difficult and expensive task. Therefore, additional compounds are added to alumina to achieve a more complex component design and to minimise the product processing and manufacturing costs. This paper examines the effects of speed, load values and the addition of Cr2O3, SiO2 and MnO2 compounds on the friction and wear behaviour of alumina ceramic. Wear tests for alumina and alumina samples containing w1.5% Cr2O3 w3% SiO2 and w1.5% MnO2 compounds was carried out on a pin‐on‐disc machine. Tribological tests were under 2.5, 5 and 10N loads and at 0.5, 0.75 and 1m/Sec speeds. The specific wear rates were deduced from mass loss. The wear rate for alumina without additional compounds was in the order of 10–8 to 10–7mm2/N, while the wear rate values for alumina with additional compounds were in the order of 10–6. Moreover, the wear rate showed more sensitivity to the applied load, particularly at low sliding speeds. Furthermore, it is concluded that a 20 per cent decrease in the sintering temperature resulted in 300 per cent increase in the specific wear rate of alumina ceramic material.
Zhishuang Wang, Songhua Li, Jian Sun, Junhai Wang, Yonghua Wang, Zhongxian Xia and Chao Wei
The purpose of this study is to investigate the effects of load and rotation speed on dry sliding of silicon nitride, including a series of tribological behaviors (friction…
Abstract
Purpose
The purpose of this study is to investigate the effects of load and rotation speed on dry sliding of silicon nitride, including a series of tribological behaviors (friction coefficient, wear rate, temperature rise, etc.) and wear mechanism. Through the analysis of the above characteristics, the influence law of load and speed on them and the internal relationship between them are determined, and then the best comprehensive performance parameters of silicon nitride full-ceramic spherical plain bearings in dry sliding are predicted, which can provide guidance for the operation condition of silicon nitride full-ceramic spherical plain bearings in dry sliding.
Design/methodology/approach
The experimental study of different loads and rotation speeds under dry friction conditions was carried out by the using ball-disk sliding test method.
Findings
With the increase of load, the friction coefficient of silicon nitride friction pair and the wear rate of silicon nitride ball decrease continuously. With the increase of rotation speed, the friction coefficient of silicon nitride friction pair first increases and then decreases, and the wear of silicon nitride ball first increases and then decreases. With the increase of load and rotation speed, the wear mechanism eventually changes to adhesive wear.
Originality/value
Because of the low timeliness and inefficiency of bearing experiments, this work adopts a simple ball-disk model to comprehensively explore the influence rules of different conditions, which provides a theoretical basis for the subsequent practical application of silicon nitride full-ceramic spherical plain bearings.
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Mathias Woydt, Bernard Criqui, Gérard Desplanches and Tom Linneman
The purpose of this paper is to underline the future need for OEMs to receive lowSAP, polymer‐ and metal‐free engine oils with high‐viscosity indices and to illuminate for other…
Abstract
Purpose
The purpose of this paper is to underline the future need for OEMs to receive lowSAP, polymer‐ and metal‐free engine oils with high‐viscosity indices and to illuminate for other OEMs the technical feasibility for application of alternative engine oils based on esters or blends of hydrocarbons with esters or polyglycols.
Design/methodology/approach
The strategic goal depends technically on the use of intrinsic properties of alternative base fluids, thus substituing some additives, like anti‐wear, extreme pressure and viscosity index improvers. The prone wear resistance of novel triboactive/‐reactive materials enables higher portions of mixed/boundary lubrication generated by oils with a lower viscosity.
Findings
Overall, the different bionotox and low‐ash prototype engine oils with reduced additive contents displayed isoperformance regarding the tribological behaviour against cast iron and triboreactive materials. APS‐Tin−2Cr2O2n−1 displayed an overall wear resistance comparable with grey cast iron with high‐carbon content and liner wear reduction of one order of magnitude when mated with Mo‐based rings. Both tests confirmed the potential for substituing molybdenum‐based rings by APS‐Tin−2Cr2O2n−1. The most significant reduction in “system wear” down to “zero wear” was demonstrated by mating the APS‐Tin−2Cr2O2n−1 coated piston rings with smooth machined HVOF‐(Ti,Mo)(C,N) liner coatings.
Research limitations/implications
As lubricants are today not part of the core business of automotive OEMs, the next steps have to be proposed by the petrochemical suppliers. It is recalled here that some OEMs in their history developed and produced lubricants.
Practical implications
The customer will appreciate any increase in longevity resulting in reduced maintenance. The OEM now owns, under increased solicitations, now a future‐oriented tool box in order to respond to environmental and CAFÉ demands with reasonable cost management.
Originality/value
This OEM report displays the complete methodology in order to adopt alternative engine oils in existing engine architectures.
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Hongjin Zhao, Lei Cao, Yong Wan, Shuyan Yang, Jianguo Gao and Jibin Pu
The purpose of this paper is to increase wear resistance of aluminum.
Abstract
Purpose
The purpose of this paper is to increase wear resistance of aluminum.
Design/methodology/approach
The authors have studied the ways to improve the tribological performance of aluminum by assembling stearic acid on aluminum coated by sol-gel-derived TiO2 film. The samples were characterized by infrared spectroscopy, contact angle measurements and a macro friction and wear tester.
Findings
Enhanced wear resistance was clearly obtained after functionalization of TiO2 film on aluminum by stearic acid.
Originality/value
The relevant results might be helpful for guiding the surface modification of aluminum devices in industrial applications.
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Elyria Kemp, Steven W. Kopp and My (Myla) Bui
Brand management has traditionally enlisted visual branding elements, including the brand’s graphic logo, to distinguish and communicate the personality of the brand. However, as…
Abstract
Purpose
Brand management has traditionally enlisted visual branding elements, including the brand’s graphic logo, to distinguish and communicate the personality of the brand. However, as healthcare organizations work to shape how consumers perceive their brand, organizations are also enhancing their brand identity with sound and music by creating a sonic brand. This research paper aims to examine how sonic brands influence consumer emotional reactions and trust in a healthcare provider. It also explores how sonic brands can differentially affect consumers, depending on their level of engagement in their physical and mental health.
Design/methodology/approach
Two experimental studies were conducted that tested the use of a sonic logo for healthcare providers in consumption contexts that might elicit negative emotions, cancer care and mental health care.
Findings
The results suggest that the presence of a sonic logo helped to alleviate negative emotions as well as engender trust in the provider. Findings also revealed that for consumers who are less engaged in their health, a sonic logo served as a peripheral cue by enhancing perceptions of competence and empathy for the healthcare provider.
Originality/value
Findings from this research provide insight into how sonic brands can increase the effectiveness of branded healthcare communications.
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Steven W. Kopp and Elyria Kemp
Research on death and dying in Western culture holds that individuals engage in a denial and repression of thoughts about death. However, this paper aims to propose that some…
Abstract
Purpose
Research on death and dying in Western culture holds that individuals engage in a denial and repression of thoughts about death. However, this paper aims to propose that some individuals actively make attempts to exercise control over their eventual demise by engaging in decision-making to achieve an “appropriate death.” A framework is introduced that provides the basis for exploring aspects of decision-making for end of life.
Design/methodology/approach
Depth interviews were conducted with 18 consumers about their dispositions toward death and their decision-making regarding their own funerals.
Findings
An analysis of the consumer narratives suggests that individuals make efforts to prepare for end of life by reducing conflict and finishing business, enlisting identity management strategies and coming to terms with death itself. Unique consumption experiences and decisions accompany each of these efforts.
Research limitations/implications
This research provides understanding regarding how individuals cope with death by attempting to enlist control over a situation in which they have very little control. In doing so, these individuals make efforts to achieve an “appropriate death” by making explicit decisions for end of life.
Originality/value
Instead of actively engaging in defense mechanisms to deny and repress thoughts of death, this research demonstrates that individuals may recognize the inevitability of death as fulfillment of life. In doing so, they may subscribe to positive illusions regarding end of life and make attempts to exercise control over the event.