Effect of quenching parameters on mechanical properties of bell metal Pranay Kumar Sarkar a,⇑ , Sashindra Kumar Kakoty a,b a Center for Rural Technology, IIT Guwahati, Guwahati 781039, India b Department of Mechanical Engineering, IIT Guwahati, Guwahati 781039, India article info Article history: Received 3 October 2020 Received in revised form 15 October 2020 Accepted 19 October 2020 Available online xxxx Keywords: Bell metal Heat Treatment Quenching temperature Quenching medium Mechanical properties abstract Bell metal, also known as kanh/ kansha is a specific binary Cu-Sn alloy containing 20 – 25 percent Sn (wt. basis), find verities of applications viz., cannon, bells, utensils, artifacts etc. from prehistory time due to its golden luster and excellent reverberating property, but has hardly been investigated by engineers to increase its industrial applications. In the present study, mechanical properties namely hardness and fracture strength of bell metal quenched in different mediums from various temperature for several com- positions have been reported. The result shows that the mechanical properties of cast, oil quenched and water quenched sample increased by almost 50 percent, 30 percent and 80 percent respectively for a 5% increase in Sn percentage in composition. Further, the mechanical properties of water quenched sample increase by 50 percent on increasing the quenching temperature by 50 °C above 700 °C. Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Confer- ence on Advances in Materials Processing & Manufacturing Applications. 1. Introduction Bell metal is a Cu-Sn alloy containing 20 – 25 percent Sn (wt. basis) and 75 – 80 percent Cu (weight basis) with less than 1 per- cent other minor alloying elements, e.g., Mn, P, Fe and Si [1]. Bell metal is also known as high-tin-bronze in the archaeo- metallurgical world, b-bronze in the metallurgical industry and kanh/ kansha in India [2,3]. Different bell metal products viz., can- non, utensils, oil lamp, measuring instruments, ornaments, decora- tive items etc. are in regular use from prehistory times [4,5]. Moreover, use of bell metal utensils represents the rich cultural heritage all over India, especially in places like Assam, Kerala, Tamilnadu, Manipur, West Bengal, Gujrat, Karnataka, Rajasthan, Uttar Pradesh etc. [2,3,5]. Bell metal is the most popular material in the casting industry from ancient time because of its better flowability inside the mould and lower melting point (780–800 °C) [6]. Bell metal prod- ucts show better mechanical properties as compared to regular bronzes [4]. Srinivasan reported that bell metal products are pre- ferred to the brass products due to better non-toxicity nature and corrosion resistance [7]. Few other unique properties of bell metal viz., long-lasting golden luster, reverberating qualities etc. are also exploited to make various other products [8]. Several archaeological studies reported that the bell metal products are manufactured either by casting or by shaping with hot forging the cast ingots followed by water quenching process [4,9]. Artworks are also observed on the body of a few products dis- covered in different countries. Evidentially it is also found that all the water quenched products have composition more than 22 per- cent Sn, and others are cast [6]. The detailed technical aspects of these manufacturing processes in making of various ancient arte- facts found in India, Iran, China, Thailand, Korea etc. have been dis- cussed by numbers of researchers [3,4,6]. These studies conclude that products are made by the above two processes to outmanoeu- vre the formation of the d phase. Presence of the d phase reduces the impact strength of items and makes the products brittle. The microstructure, composition, XRD, hardness etc. of different ancient products manufactured by both the process has also been reported in several studies [2,4]. Only one published paper has come to the notice of the authors in the literature related to the study of the effects of the processing parameters on the mechanical properties of bell metal. Park et al. studied the effect of composition and quenching temperature on the hardness value of bell metal [6]. They have used water as a quenching medium. The study reported that the Rockwell hardness (B scale) value increases from 78 to 103.5 as the percentage of Sn increases from 17 percent to 22 percent in the quenched (quench- ing temperature 750 °C) Cu-Sn alloy composition. And for Cu-Sn alloy containing 20 percent Sn, the hardness value increases from https://doi.org/10.1016/j.matpr.2020.10.529 2214-7853/Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Advances in Materials Processing & Manufacturing Applications. ⇑ Corresponding author. E-mail address: pranaysarkar1@gmail.com (P.K. Sarkar). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: Pranay Kumar Sarkar and Sashindra Kumar Kakoty, Effect of quenching parameters on mechanical properties of bell metal, Mate- rials Today: Proceedings, https://doi.org/10.1016/j.matpr.2020.10.529