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The grain size and grain distribution mode have a significant impact on the tribological properties of Babbitt alloy. The purpose of this paper is to study the effect of differentiated SnSb grain size distribution on the improvement of tribological properties of Babbitt alloy.

Babbitt (marked by babbitt-cr), with a differentiated SnSb grain size distribution, was fabricated using a selective zone laser surface treatment. Bare Babbitt with coarse SnSb grain was marked as babbitt-c, and Babbitt with refined SnSb grain was marked as babbitt-r. The microstructure, microhardness and wettability of specimens were tested. The tribological properties of babbitt-c, babbitt-r and babbitt-cr were evaluated under dry and lubricated conditions.

The microstructure transforms from single coarse SnSb grain distribution or single refined SnSb grain distribution to differentiated SnSb grain size distribution, as a result of selective zone laser surface treatment. Among three specimens of microhardness, babbitt-cr showed the highest microhardness. The lipophilicity property of babbitt-cr was better compared to babbitt-c. A mixture of coarse and refined grain is beneficial to improve the tribological properties of Babbitt alloy under dry condition. Furthermore, compared with babbitt-c, the wear resistance of babbitt-cr was enhanced under lubricated condition. However, the anti-wear property of babbitt-cr was not significantly improved relative to babbitt-r with an increase in the loads.

The study demonstrates that modulated different grain size alternating distribution modes can improve the tribological properties of Babbitt alloy.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2022-0259/

Observation by optical microscopy and EBSP have made it clear that the trigger for the grain coarsening phenomenon of austenite stainless steel BS304S31 may be the stacking faults concentrating selectively in a thin layer lying just beneath the grain boundary. When macroscopic plastic strain reached 6 percent, selective concentration of stacking faults was observed. When it reached 20 percent, the distribution of stacking faults became uniform in each grain. After these specimens were heated, concentration of stacking faults disappeared, and grain coarsening occurred at the point with 6 percent strain, but no grain coarsening occurred at the point with 20 percent strain. In order to investigate this concentration of stacking faults, an attempt was made to analyze the deformation in each crystal by using image‐based FEM. The result suggested that there is a possibility that plastic strain concentrates in the vicinity of the grain boundary when the macroscopic plastic strain is small.

The purpose of this paper is to realize dynamical grey incidence order of influencing factors of grain production in Henan province using grey systems theory.

Starting from choosing influence factors on grain production and dividing the 30 years (from 1979 to 2009 year) of grain production in Henan province into three periods, the authors calculate grey incidence degree between grain yield and every influencing factor by grey incidence analysis method, respectively, then obtain the grey incidence order of influencing factors in every period. Also based on the three grey incidence orders from different periods, the authors find a changeable tendency of influencing factors on grain production and key influencing factors on grain production in different periods. Finally, to keep Henan province grain production stable and sustainable, several policy suggestions are given.

The results are convincing: it is effective and powerful to analyze dynamically influencing factors of grain production using grey systems theory, and it is urgent to strengthen agricultural science and technology input, and pay close attention to the influence of dosage of pesticide and fertilizers on grain production.

Grey incidence analysis and findings exposed in the paper can be used by agricultural firms to optimize grain production plans, and by government to formulate reasonable agricultural production policies.

The paper succeeds in getting dynamical grey incidence order of influencing factors of grain production in Henan province using grey systems theory.

A new model to describe dopant diffusion and recrystallisation in polycrystalline silicon during thermal treatment is presented. The full 3D microstructure of the material is considered and a local homogenisation approximation introduced. A parallel diffusion model for diffusion in grain boundaries and grain interior with grain growth and segregation is developed within this approximation. The model is solved in a 2D vertical section using a finite element discretisation. An example of the application of this model to a one micron bipolar transistor is given.

As one of its major strategies, China has made a new plan to further expand High Standard Farmland (HSF) to all permanent basic farmland (80% of total farmland) for grain security over the next decade. Yet, what will be the impact of farmland infrastructure investment on agrifood systems? The paper aims to systematically evaluate the multiple effects (food security, economy, nutrition and environment) of expanding HSF construction under the context of the “Big Food vision” using an interdisciplinary model.

An interdisciplinary model – AgriFood Systems Model, which links the China CGE model to diet and carbon emission modules, is applied to assess the multiple effects of HSF construction on agrifood systems, such as food security and economic development, residents’ diet quality and carbon emissions. Several policy scenarios are designed to capture these effects of the past HSF investment based on counterfactual analysis and compare the effects of HSF future investment at the national level under the conditions of different land use policies – restricting to grain crops or allowing diversification (like vegetables, and fruit).

The investments in HSF offer a promising solution for addressing the challenges of food and nutrition security, economic development and environmental sustainability. Without HSF construction, grain production and self-sufficiency would decline significantly, while the agricultural and agrifood systems’ GDP would decrease. The future investment in the HSF construction will further increase both grain production and GDP, improve dietary quality and reduce carbon emissions. Compared with the policy of limiting HSF to planting grains, diversified planting can provide a more profitable economic return, improve dietary quality and reduce carbon emissions.

This study contributes to better informing the impact of land infrastructure expanding investment on the agrifood systems from multiple dimensions based on an interdisciplinary model. We suggest that the government consider applying diversified planting in the future HSF investment to meet nutritional and health demands, increase household income and reduce carbon emissions.

This paper explores the contested notion of what constitutes a fair price in the context of grain exchanges in a subsistence farming village in the highlands of Matagalpa. Using ethnographic data, I show how Nicaraguan campesinos’ economic behavior plays out within a local moral universe of fairness: how much to produce and how much to sell in the market (or to give away); how prices and obligations vary depending on the social relation that binds the seller and the buyer (kinship, friendship, community, and so on); in what ways these notions of fair price are articulated and contested by different classes within a rural community; and lastly, what is expected of the State in terms of regulating food prices. Price emerges as the dialectic between the market in its abstract form and the specific social relationships and everyday politics that shape exchanges. What constitutes help (ayuda) and what constitutes exploitation in market exchanges and the determination of price is constantly contested, the moral economy is a discursive battlefield.

This paper compares grain prices between Cairo and Europe during medieval times. Prices were higher and more volatile in Cairo than in Europe. Over time, price levels declined in large parts of Europe but not in Cairo.

No price integration can be seen between the European Mediterranean region and Cairo. In north-western Europe, a cluster of urban centers showing similar price movements had emerged in the fourteenth century, at the latest. The Mediterranean area was not integrated into this network. Price integration in north-western Europe may have contributed to the economic advancement of this region in late medieval and early modern times.

Climatic fluctuations (in temperature as well as in the water level of the Nile) affected Cairo grain prices. In Europe, on the other hand, short-term temperature variation did not have an appreciable impact on prices. Western European price integration cannot, it seems, be explained by the existence of a common climatic factor. Early European economic development was facilitated by a robust environment.

This paper attempts to understand how the interaction of natural disasters and human behaviour during wartime led to famines in three regions under imperial control around the Indian Ocean. The socio-economic structure of these regions had been increasingly differentiated over the period of imperial rule, with large proportions of their populations relying on agricultural labour for their subsistence.

Before the war, food crises in each of the regions had been met by the private importation of grain from national or overseas surplus regions: the grain had been made available through a range of systems, the most complex of which was the Bengal Famine Code in which the able-bodied had to work before receiving money to buy food in the market.

During the Second World War, the loss of control of normal sources of imported grain, the destruction of shipping in the Indian Ocean (by both sides) and the military demands on internal transport systems prevented the use of traditional famine responses when natural events affected grain supply in each of the regions. These circumstances drew the governments into attempts to control their own grain markets.

The food crises raised complex ethical and practical issues for the governments charged with their solution. The most significant of these was that the British Government could have attempted to ship wheat to Bengal but, having lost naval control of the Indian Ocean in 1942 and needing warships in the Atlantic and Mediterranean in 1943 chose to ignore the needs of the people of Bengal, focussing instead on winning the war.

In each of the regions governments allowed/encouraged the balkanisation of the grain supply – at times down to the sub-district level – which at times served to produce waste and corruption, and opened the way for black markets as various groups (inside and outside government ranks) manipulated the local supply.

People were affected in different ways by the changes brought about by the war: some benefitted if their role was important to the war-effort; others suffered. The effect of this was multiplied by the way each government ‘solved’ its financial problems by – in essence – printing money.

Because of the natural events of the period, there would have been food crises in these regions without World War II, but decisions made in the light of wartime exigencies and opportunities turned crises into famines, causing the loss of millions of lives.

In recent years, additive manufacturing (AM) has started to be used for manufacturing real functional parts and assemblies for critical applications in aerospace, automotive, and machinery industries. Most complex or assembled parts require internal features (IF) such as holes, channels, slots, or guides for locational and mating requirements. Therefore, it is critical to understand and compare the structural and mechanical properties of additively manufactured and conventionally machined IFs.

In this study, mechanical and microstructural properties of Inconel 718 (Inc718) alloy internal features, manufactured either as-built with AM or machining of additively manufactured (AMed) part thereafter were investigated.

The results showed that the average ultimate tensile strength (UTS) of additively manufactured center internal feature (AM-IF) is almost analogous to the machined internal feature (M-IF). However, the yield strength of M-IF is greater than that of AM-IF due the greater surface roughness of the internal feature in AM-IF, which is deemed to surpass the effect of microstructure on the mechanical performance. The results of digital image correlation (DIC) analysis suggest that AM-IF and M-IF conditions have similar strain values under the same stress levels but the specimens with as built IF have a more locally ductile region around their IF, which is confirmed by hardness test results. But this does not change global elongation behavior. The microstructural evolution starting from as-built (AB) and heat-treated (HT) samples to specimens with IF are examined. The microstructure of HT specimens has bimodal grain structure with d phase while the AB specimens display a very fine dendritic microstructure with the presence of carbides. Although they both have close values, machined specimens have a higher frequency of finer grains based on SEM images.

It was shown that the concurrent creation of the IF during AM can provide a final part with a preserved ultimate tensile strength and elongation but a decreased yield strength. The variation in UTS of AM-IF increases due to the surface roughness near the internal feature as compared to smooth internal surfaces in M-IF. Hence, the outcomes of this study are believed to be valuable for the industry in terms of determining the appropriate production strategy of parts with IF using AM and postprocessing processes.

Understanding and tailoring the solidification characteristics and microstructure evolution in as-built parts fabricated by laser powder bed fusion (LPBF) is crucial as they influence the final properties. Experimental approaches to address this issue are time and capital-intensive. This study aims to develop an efficient numerical modeling approach to develop the process–structure (P-S) linkage for LPBF-processed Inconel 718.

In this study, a numerical approach based on the finite element method and cellular automata was used to model the multilayer, multitrack LPBF build for predicting the solidification characteristics (thermal gradient G and solidification rate R) and the average grain size. Validations from published experimental studies were also carried out to ensure the reliability of the proposed numerical approach. Furthermore, microstructure simulations were used to develop P-S linkage by evaluating the effects of key LPBF process parameters on G × R, G/R and average grain size. A solidification or G-R map was also developed to comprehend the P-S linkage.

It was concluded from the developed G-R map that low laser power and high scan speed will result in a finer microstructure due to an increase in G × R, but due to a decrease in G/R, columnar characteristics are also reduced. Moreover, increasing the layer thickness and decreasing the hatch spacing lowers the G × R, raises the G/R and generates a coarse columnar microstructure.

The proposed numerical modeling approach was used to parametrically investigate the effect of LPBF parameters on the resulting microstructure. A G-R map was also developed that enables the tailoring of the as-built LPBF microstructure through solidification characteristics by tuning the process parameters.