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Binder jetting of 17-4PH martensitic stainless steel is of great interest to several industries that could exploit the higher degree of geometrical complexity granted by 3D printing, thus this paper aims at providing a comprehensive description of the material development throughout the multiple manufacturing stages and treatments.

In this work, insight into the as-sintered 17-4PH microstructure and the manufacturing process effects on the copper precipitation is provided. Furthermore, conventional ageing treatments were applied to the specimens starting from either the as-sintered or the solution-annealed state and studied with particular attention to the microstructure and the resulting mechanical properties.

The analysis of the as-sintered microstructure revealed a continuous δ ferrite network along martensitic grains, with Cu-rich phases within the ferritic phase. Solution annealing was able to redistribute the alloying elements within the matrix and limit the continuity of the ferritic network leading to an enhancement in ductility. On the contrary, the direct ageing treatments performed on the as-sintered microstructure lead to overageing of the Cu-precipitates and impairing of the tensile properties compared to those starting from solution annealed condition. Nonetheless, hardness remains comparable independently from the ageing temperature and the ferritic network retains its morphology and distribution.

A stepwise description of the microstructural development throughout thermal treatments is provided granting the chance to design the most convenient post-processing route to achieve the required mechanical properties with a minimisation of energy and cost consumption.

The anti-friction and anti-wear properties of WS₂@GO composites on paraffin liquid were investigated with a four-ball tribometer.

A series of graphene oxide (GO) nano hybrid composites decorated with tungsten disulfide (WS₂) were prepared in-suit by hydrothermal strategy.

The results showed that compared to the virgin oil, friction coefficient and diameter of wear scare of lubricant oil containing W/G = 1:1 hybrid composite was reduced by 42.7% and 31.6%, respectively. At the microscopic, the excellent lubrication performance resulted from the tribo-chemical reaction on the sliding interface, which promotes the formation of tribo-film with a thickness of 8 nm. The carbonization compound, WO₃ and Fe₂O₃ in the tribo-film results from the tribo-chemical reactions at the sliding interface, which can improve the stability and strength of tribo-film. Thereby the metal surface was further protected from friction and wear.

A series of WS₂@GO composites were prepared in-suit by a hydrothermal strategy, and the tribo-film was analyzed by the transmission electron microscope and X-ray photoelectron spectrometer.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2024-0397

This study aims to shed light on how artificial intelligence based on robust algorithms is used in providing public services and the public’s fears about dealing with these systems. The challenges facing governments that use these systems are accountability, transparency, integrity and addressing errors in advanced technologies.

This study used the descriptive approach to describe and analyze public procurement and how public service systems are purchased. The analytical approach was also used to analyze the problems and issues that could result from using artificial intelligence in providing public services regarding concerns about its use and issues of transparency, access to information, accountability and responsibility.

The government sector must uphold rights, freedoms, human rights and the rule of law, as well as a commitment to justice, responsibility, integrity, transparency, accountability and openness if this paper use private AI systems. These AI systems will still have the motivations and ideals of the organization and their creators. Accountability systems and governance processes are still needed. Therefore, developing these technologies in-house is not the solution to corporate adoption and interconnection. AI procurement requirements and documentation should apply to internal and external development scenarios.

This study outlined the difficulties public bodies have when purchasing AI systems and the long-term effects that call for developing procurement policies and procedures tailored to the needs of AI. Future studies might analyze the advantages and disadvantages of openness, particularly regarding disclosures made to the public. In what ways are disclosures made to the public aid in AI system governance? What restrictions apply to disclosures? Is it possible to use new forms of emerging technology to help the public engage meaningfully in discussions about due process and fundamental rights?