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Particularly during machining, large heat sources and thus high temperature gradients and mechanical stress occur in the cutting zone. By using cutting fluids, part of the heat generated can be dissipated, thereby reducing local temperatures. To quantify the cooling efficiency of the cutting fluid, the flow behaviour of the cutting fluid in vicinity of the cutting zone must be determined to derive the resulting convective heat transfer coefficients at the tool. The purpose of this paper is to investigate the local distribution of the convective heat transfer coefficient as a function of the flow boundary conditions, specifically evaluating the effects of Reynolds number, injection angle and nozzle radius.

The geometries, temperature fields as well as the heat sources resulting during the machining process are extracted from a chip formation simulation using finite element method (FEM) and used to set up a three-dimensional computational fluid dynamics (CFD) flow simulation.

On the tool rake face, the local distribution of the convective heat transfer coefficient can be divided into three regions. Firstly, the region where the liquid impinging jet initially strikes, then a region near the chip where the flow is strongly deflected and then the remaining region in the boundary layer region. For each region, a function is derived that describes its position, subsequently the mean convective heat transfer coefficient is determined and summarised in a Nusselt correlation as a function of the flow parameters.

Simulation results reveal that the distribution of the convective heat transfer coefficient on the tool rake face can be divided into three distinct regions: the impingement zone where the impinging jet first strikes, the deflection zone near the chip where the flow sharply redirects and the boundary layer zone covering the remaining surface. A geometric function is derived to describe the position and extent of each of these areas. In addition, the mean convective heat transfer coefficient can be determined for each of the regions using a Nusselt correlation based on the flow parameters.

These correlations allow for simplified determination of the local convective heat transfer coefficient on the tool.

This paper introduces an innovative approach for estimating the local distribution of the convective heat transfer coefficient at the tool rake face during orthogonal cutting under cutting fluid supply. The influence of the three-dimensional flow field of the cutting fluid jet of the convective heat transfer coefficient on the tool rake face is analysed in detail in the vicinity of the chip as a function of varying Reynolds numbers, nozzle radii and injection angles within a three-dimensional geometry.

The purpose of this study is to draw a scientific map of the Grand Tours cycling as part of the growing research field in this field at the global level. This study also identifies the components of scientific production in this field along with their collaboration patterns.

With the aim of achieving a comprehensive and deep understanding of the studies related to the Grand Tour, this research aims to address the existing gaps and provide a comprehensive summary of these scholarly works. To achieve this goal, the authors used a systematic and scientometric combination method, analyzing studies from the past half century (1970–2022).

The research findings reveal that scientific studies related to cycling events exhibit a geographical concentration within the continent of Europe, surpassing other continents. Notably, Spain, the USA, the UK and Italy emerge as pioneers in this field of inquiry. The main themes identified in these studies encompass cycling, the Tour de France, performance, professional roa cycling, heart rate, endurance, doping and power output.

This research, along with other systematic studies, contributes to the existing literature in this field by providing both quantitative and qualitative data. Additionally, the study serves as a foundation for identifying active and influential countries, institutions and authors in this domain. Such insights are highly effective in establishing scientific focal points in this field.

This study, in conjunction with the introduction of key figures in mega cycling event research, sheds light on the thematic areas explored within these studies. Notably, it is the sole study that has illuminated hidden facets of this field using scientometric and systematic methods.

High-performance wrought aluminum alloys, particularly AA6061, are pivotal in industries like automotive and aerospace due to their exceptional strength and good response to heat treatments. Investment casting offers precision manufacturing for these alloys, because casting AA6061 poses challenges like hot cracking and severe shrinkage during solidification. This study aims to address these issues, enabling crack-free investment casting of AA6061, thereby unlocking the full potential of investment casting for high-performance aluminum alloy components.

Nanotechnology is used to enhance the investment casting process, incorporating a small volume fraction of nanoparticles into the alloy melt. The focus is on widely used aluminum alloy 6061, utilizing rapid investment casting (RIC) for both pure AA6061 and nanotechnology-enhanced AA6061. Microstructural characterization involved X-ray diffraction, optical microscopy, scanning electron microscopy, differential scanning calorimetry and energy dispersive X-ray spectroscopy. Mechanical properties were evaluated through microhardness and tensile testing.

The study reveals the success of nanotechnology-enabled investment casting in traditionally challenging wrought aluminum alloys like AA6061. Achieving crack-free casting, enhanced grain morphology and superior mechanical properties, because the nanoparticles control grain sizes and phase growth, overcoming traditional challenges associated with low cooling rates. This breakthrough underscores nanotechnology's transformative impact on the mechanical integrity and casting quality of high-performance aluminum alloys.

This research contributes originality and value by successfully addressing the struggles in investment casting AA6061. The novel nano-treating approach overcomes solidification defects, showcasing the potential of integrating nanotechnology into rapid investment casting. By mitigating challenges in casting high-performance aluminum alloys, this study paves the way for advancements in manufacturing crack-free, high-quality aluminum alloy components, emphasizing nanotechnology's transformative role in precision casting.