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This paper aims to report the production of 316L-1 Wt.% NiB cubes by using the selective laser melting (SLM) process. The laser used was pulsed, millisecond Nd:YAG system with maximum average power 100 W.

Densification under different processing conditions (pulse energy, average laser power, laser scan speed, powder layer thickness, pulse frequency) was investigated. Morphology, macro and microstructure of laser melted samples were characterized by digital camera images and by scanning electron microscope. Density of the cubes was determined by Archimedes method in water. Vickers microhardness of samples was determined under the load of 25 g. Corrosion behavior of 316L and 316L-NiB samples was conducted in 5 per cent HCl solution at the testing temperature of 20°C during 240 h.

Using laser power of ∼60-70 W, lower beam overlap and powder layer thickness of 200 µm, 3D cubical samples were obtained with significant balling in individual layers and an overall porosity being around 30 per cent. By increasing laser power to ∼80 W, with higher beam overlap and lower powder layer thickness of 100 µm, SLM parts with no balling and the presence of small pores of up to 4 per cent (20 Hz) and 9 per cent (40 Hz) were obtained. With further increase of laser power to 90 W, overall porosity rose to around 12 per cent. The addition of 1 Wt.% NiB to stainless steel negligibly lowered its corrosion resistance in 5 per cent HCl solution.

A part from 316L stainless steel with balling-free structure and good density was successfully obtained through pulsed-SLM process with the aid of 1 Wt.% of NiB addition. Aside from significant influence on the improved structure of cubes, NiB had a favorable effect on microhardness values while practically not affecting the corrosion resistivity of the base material in an aggressive surrounding.

The purpose of this paper is to focus on Sarajevo, the capital of Bosnia and Herzegovina, giving a general overview of its urban context through five historical periods, as part of a research study on its modernist architectural heritage.

Designed to mimic the theatrical process which unfolds through acts and intervals, the paper combines literary, architectural, journalistic and historical sources, to sketch the key periods which characterise the city’s urban morphology.

The sequence of acts and intervals points to the dramatic historic inter-change of continuities and ruptures, in which the ruptures have often been less studied and understood. This explains the frequent conceptualising of Sarajevo through East–West binary, which synthesises it as a provincial capital from Ottoman and later Habsburg rule, a regional centre within two Yugoslav states and a capital city of a young state of Bosnia and Herzegovina. This highlights the need to study the ruptures as clues to the flow of continuities, in which the care and after care for built environment provide a field of evidence and possibilities for diverse perspectives of examination.

Corroborated by secondary sources, the paper examines the accounts of urban heritage destruction in the 1990s war, as recorded by a writer, an architect and a journalist, and outlines a pattern of unbroken inter-relations between urban and architectural space (tangible) and sense and identity of place (intangible).

This discourse is relevant to the current situation where the city of Sarajevo expands again, in the complexity of a post-conflict society.

Challenged by the political divisions and the laissez-faire economy, the public mood and interest is under-represented and has many conflicting voices.

Inspired by Italo Calvino’s Invisible Cities and the accounts from the siege of Sarajevo in the 1990s, this conceptual paper contributes to the formulation of a cross-disciplinary discursive prism through which the fragments of the city and its periods come together or apart, adding, subtracting and changing layers of meaning of the physical space.