Shuaishuai Zhu, Baosen Zhang, Zhixin Ba, Xiangyang Mao, Weijie Fei and Zhangzhong Wang
This paper aims to investigate the friction and wear properties of Cr-Ni-Mo-V steel against 440C stainless steel under both water and water–silica mixture lubricant.
Abstract
Purpose
This paper aims to investigate the friction and wear properties of Cr-Ni-Mo-V steel against 440C stainless steel under both water and water–silica mixture lubricant.
Design/methodology/approach
The Cr-Ni-Mo-V steel specimens were taken from a forged steel brake disc with the process of quenching at 900°C and tempering at 600°C. The tribological testing was performed using a contact configuration of ball-on-flat with a liquid cell according to the ASTM standard. Detailed examinations on the worn surface were analyzed using a scanning electron microscope.
Findings
The results indicate that the friction coefficient and friction damage of the steel sliding under water–silica mixture are higher than those under water. The friction coefficient decreases with increasing load and increases with the sliding speed for the two lubricants. The mass wear rate presents a rising trend with both sliding load and speed. The wear mechanisms of the Cr-Ni-Mo-V steel sliding under the two lubricants are oxidation wear, abrasive wear and fatigue wear.
Research limitations/implications
Because of the chosen tribological testing approach, the research results could not describe the tribological performance of the brake disc accurately during actual braking process of the high-speed train. Therefore, researchers are encouraged to test the proposed propositions further.
Originality/value
This study shows that the tribology behavior of the Cr-Ni-Mo-V steel with water or water–silica mixture lubrications helps the industrial firms and academicians to work on the wear of the brake disc in rainwater or wet environment.
Details
Keywords
In recent years, with the rapid development of the Internet and e-commerce, the online retail business has grown rapidly. E-commerce platforms can track different click data to…
Abstract
Purpose
In recent years, with the rapid development of the Internet and e-commerce, the online retail business has grown rapidly. E-commerce platforms can track different click data to understand consumer behavior and demand preferences, so as to make better demand forecasts, and strategically share this information with upstream suppliers. When the platform charges a certain fee for the shared data, the suppliers face the question of whether to purchase demand information. This article aims to analyze the influence of price competition and advertising competition on the suppliers' decisions to purchase information and the online platform for data pricing.
Design/methodology/approach
By using static game with incomplete information, this paper explores information-sharing strategies of an online platform with two competitive brand suppliers. The authors use Nash game to analyze the suppliers' purchasing information decision and then obtain the optimal information price of the online platform with information-sharing contract.
Findings
This paper shows that demand information sharing benefits both the platform and the suppliers. Without information contracts, the online platform is willing to share demand information with at least one supplier. Especially, when the consumer's sensitivity to advertising is larger and the commission fee charged by the online platform is small, the online platforms will share information with only one supplier. Based on the game outcomes between the suppliers, two pricing strategies for information are proposed under which at least one supplier purchases information. If the consumers are less (more) sensitive to advertising competition, pricing strategy of the online platform induces both suppliers (only one supplier) to purchase information.
Originality/value
At present, most of the information-sharing articles are based on the traditional purchase and sale mode. Based on the background of e-commerce, this paper examines the online platform's information-sharing strategies, which has certain innovation. In addition, the results show that the information-sharing strategy of the online platform is affected by both the price and advertising competitiveness, which provides a new expansion and supplement for the information-sharing literature.