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This paper presents the application of grey modeling for thermal spray processing parameter analysis in less data environment.

Based on processing knowledge, key processing parameters of thermal spray process are analyzed and preselected. Then, linear and non-linear grey modeling models are integrated to mine the relationships between different processing parameters.

Model A reveals the linear correlation between the HVOF process parameters and the characterization of particle in-flight with average relative errors of 9.230 percent and 5.483 percent for velocity and temperature.

The prediction accuracies of coatings properties vary, which means that there exists more complex non-linear relationship between the identified input parameters and coating results, or more unexpected factors (e.g. factors from material side) should be further investigated.

According to the modeling case in this paper, method has potential to deal with other diverse modeling problems in different industrial applications where challenge to collecting large quantity of data sets exists.

It is the first time to apply grey modeling for thermal spray processing where complicated relationships among processing parameters exist. The modeling results show reasonable results to experiment and existing processing knowledge.

The purpose of this paper is to explore selective laser melting of yttria-stabilized zirconia (YSZ) ceramic by a 1 μm wavelength fibre laser; investigate the influence of different laser powers and different scanning velocities on the microstructure, the relative density, the deformation of ceramic sample and the micro-hardness; and analyze the crystal structure transformation during the fabrication.

During the fabrication, the 5 mm × 5 mm × 5 mm YSZ ceramic samples are fabricated by rapid prototyping (RP) machine MCP Realizer SLM 250; density and microscopic photographs show the ceramic melting situation. The density of cubic sample with different laser powers and different scanning velocities is measured by Archimedes method. The microstructure of samples and powder is observed by SEM. The micro-hardness is measured by the Vickers micro-hardness equipment, and the crystal structure transition is studied by XRD.

It is possible to melt YSZ powder completely with near-IR fibre laser, and the relative density of 5 mm × 5 mm × 5 mm cubic sample is 88 per cent, and the micro-hardness could reach 1,209 ± 262 HV₅₀₀. The influence of laser power on the volume deformation is more sensitive than the scanning speed at the same energy density. The small pores and the obvious orderly cracks can be observed in the cross-section of sample; the uneven distribution of laser energy input is the main reason of the formation of orderly cracks. The transformation from monoclinic and cubic crystal to tetragonal crystal occurred during the melting process. Heat treatment (1400°C for 30 min) cannot significantly improve the density of the sample, but it can restore the colour of ceramic.

Particularly serious due to the deformation of the ceramic material, the authors cannot prepare a large ceramic sample and measure its macroscopic mechanical properties.

This paper describes the manufacture of YSZ ceramic sample by SLM technology with a 1 μm wavelength fibre laser, and preliminary studies show the microscopic structure, distribution of laser parameters and crystal transformation.

The purpose of this paper consists in the optimization and understanding of the Selective Laser Melting (SLM) manufacturing process of biomaterials, such as T40 and CoCrMo, as scaffolds. Moreover, process optimization is also challenging, with regards to the huge number of parameters and their influence on the finished product.

The paper opted for an exploratory study using Taguchi analysis method to precisely identify the most relevant parameters and justify the energy estimation.

The study showed that SLM fits perfectly with the T40 and CoCrMo part manufacturing. This method allowed to have a complete overview of all the potential applications of SLM for implant manufacturing.

With this research approach, the results may be generalized to other material and showed a good theoretical approach.

This exploratory research aims to analyze sustainable innovation in the context of inclusive business in Latin America.

The study performs a summative content analysis of 22 inclusive businesses (IBs) of current Business Call to Action (BCtA) members in Latin America. Codes were created to identify the modification or introduction of sustainable products/services/processes. Data were analyzed using NVivo 12.

Results show a prevalence of Colombian examples within Latin American inclusive business, and a more significant proportion in the agricultural sector, consistent with reports found in the literature. The authors found that sustainable innovation takes place when introducing new products/services/processes that respond to the needs of the bottom of the pyramid (BoP) population, or modifying existing processes and services to make them more sustainable.

As most sustainable innovation literature is product-oriented and technically dominated, these results contribute to the newer works adopting a more comprehensive conception of innovation, providing empirical evidence at the product, service and process levels. The results provide insights on how inclusive businesses make adaptations to improve the sustainability of their supply chains to bring their products/services within reach of isolated and disadvantaged communities. The findings also suggest that sustainable product innovation in an inclusive business goes beyond a cost reduction objective. Tailored design reveals a hybrid socioeconomic goal with a high degree of local context embeddedness and precise attention to nascent specialized demand. The results could be of practical use for organizations that want to operate an inclusive business in BoP markets.