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1 – 2 of 2Agnieszka Chmielewska, Bartlomiej Adam Wysocki, Elżbieta Gadalińska, Eric MacDonald, Bogusława Adamczyk-Cieślak, David Dean and Wojciech Świeszkowski
The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium…
Abstract
Purpose
The purpose of this paper is to investigate the effect of remelting each layer on the homogeneity of nickel-titanium (NiTi) parts fabricated from elemental nickel and titanium powders using laser powder bed fusion (LPBF). In addition, the influence of manufacturing parameters and different melting strategies, including multiple cycles of remelting, on printability and macro defects, such as pore and crack formation, have been investigated.
Design/methodology/approach
An LPBF process was used to manufacture NiTi alloy from elementally blended powders and was evaluated with the use of a remelting scanning strategy to improve the homogeneity of fabricated specimens. Furthermore, both single melt and up to two remeltings were used.
Findings
The results indicate that remelting can be beneficial for density improvement as well as chemical and phase composition homogenization. Backscattered electron mode in scanning electron microscope showed a reduction in the presence of unmixed Ni and Ti elemental powders in response to increasing the number of remelts. The microhardness values of NiTi parts for the different numbers of melts studied were similar and ranged from 487 to 495 HV. Nevertheless, it was observed that measurement error decreases as the number of remelts increases, suggesting an increase in chemical and phase composition homogeneity. However, X-ray diffraction analysis revealed the presence of multiple phases regardless of the number of melt runs.
Originality/value
For the first time, to the best of the authors’ knowledge, elementally blended NiTi powders were fabricated via LPBF using remelting scanning strategies.
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Anna Białek-Jaworska and Agnieszka Krystyna Kopańska
This paper aims to determine whether local governments (LGs) use non-consolidated municipally owned companies (MOCs), excluded from public sector entities and, consequently, from…
Abstract
Purpose
This paper aims to determine whether local governments (LGs) use non-consolidated municipally owned companies (MOCs), excluded from public sector entities and, consequently, from sub-national debt to avoid fiscal debt limits. This paper contributes to the literature by analysing the fiscal debt rule’s impact on the off-budget municipal activities in total and separate in different types of local government units.
Design/methodology/approach
This paper uses difference-in-differences and the system general method of moments model with the Blundell–Bond estimator for dynamic panel data analysis of MOCs owned by 866 Polish municipalities in 2010–2018.
Findings
This paper shows that the MOCs’ revenues support limited local public debt capacity by indebtedness restrictions imposed on municipalities in 2014. As a result, less indebted municipalities have higher off-budget revenues. The tightening of fiscal rules related to sub-sovereign indebtedness increased off-budget activities, but that effect is much stronger in rural and rural–urban municipalities than in urban municipalities and big cities.
Originality/value
This paper contributes to the literature by exploring the fiscal debt rule’s impact on the off-budget municipal activities in total and separate in different types of local government units. In this paper, the authors combine theories relating to private and public finance; this is a novel approach and one that is also necessary – as, in fact, the worlds of public and private actors intersect – as exemplified by the existence of MOC.
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