In this paper, dense Cu–15Ni–8Sn alloy blanks were fabricated by laser-directed energy deposition (L-DED). Then, we systematically compared the L-DED sample with the laser-powder bed fusion (L-PBF) Cu–15Ni–8Sn alloy sample prepared in our previous work in terms of their building rate, microstructure, and performance. The average grain size of the L-DED sample was about 23.3 ± 16.7 μm, and its microstructure mainly included fine dendrites with a width of 5.6 ± 1.2 μm. The Vickers hardness, yield strength, and elongation at break of the L-DED sample were 166 ±5HV1, 327 ±9 MPa and 23.9 ± 3.2%, respectively. The building rate of L-DED was about 16 times that of L-PBF. Due to the different laser power densities and different melting modes of L-DED and L-PBF, there were various preferred orientations along the laser scanning direction. Compared with the L-PBF sample, the sizes of grains, dendrites, and segregated phases of the L-DED sample coarsened, and its dislocation density decreased. Combined, these factors decreased its yield strength and were primarily responsible for the lower cooling rate of L-DED. The slow cooling rate alleviated the local thermal deformation in the L-DED sample, which reduced the possibility of stress concentration and increased its plasticity and work hardening rate.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Trend of Research in the Nonferrous IndustryPaul D. MericaCite this: Ind. Eng. Chem. 1923, 15, 9, 895–897Publication Date (Print):September 1, 1923Publication History Published online1 May 2002Published inissue 1 September 1923https://pubs.acs.org/doi/10.1021/ie50165a009https://doi.org/10.1021/ie50165a009research-articleACS PublicationsRequest reuse permissionsArticle Views8Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

II. Thermal expansion of alpha and of beta brass 574 1 .

3 II.Manufacture of tinned sheet copper 5 III.Structure of tin coatings on copper 6 IV.Electrolytic potential and corrodibility of the constituents of the tin coating 10 V. Discussion and conclusions 15

Hydrothermal activity is common in the fishing port of Nagahama Bay, a small semi-enclosed bay located on the southwest coast of Satsuma Iwo-Jima Island (38 km south of Kyushu Island, Japan). The bay contains red-brown iron oxyhydroxides and thick deposits of sediment. In this work, the high concentration and sedimentation rates of oxyhydroxide in this bay were studied and the sedimentary history was reconstructed. Since dredging work in 1998, a thickness of ~ 1.0–1.5 m of iron oxyhydroxide-rich sediments has accumulated on the floor of the bay. To estimate the volume of iron oxyhydroxide sediments and the amount discharged from hydrothermal vents, sediment traps were operated for several years and 13 sedimentary core samples were collected to reconstruct the 10-year sedimentary history of Nagahama Bay. To confirm the timing of sedimentary events, the core data were compared with meteorological records obtained on the island, and the ages of characteristic key beds were thus identified. The sedimentation rate of iron oxyhydroxide mud was calculated, after correcting for sediment input from other sources.The sediments in the 13 cores from Nagahama Bay consist mainly of iron oxyhydroxide mud, three thick tephra beds, and a topmost thick sandy mud bed. Heavy rainfall events in 2000, 2001, 2002, and 2004–2005 coincide with tephra beds, which were reworked from Iwo-Dake ash deposits to form tephra-rich sediment. Strong typhoon events with gigantic waves transported outer-ocean-floor sediments and supplied quartz, cristobalite, tridymite, and albite sands to Nagahama Bay. These materials were redeposited together with bay sediments as the sandy mud bed.Based on the results from the sediment traps and cores, it is estimated that the iron oxyhydroxide mud accumulated in the bay at the relatively rapid rate of 33.3 cm/year (from traps) and 2.8–4.9 cm/year (from cores). The pore water contents within the sediment trap and core sediments are 73%–82% and 47%–67%, respectively. The estimated production of iron oxyhydroxide for the whole fishing port from trap cores is 142.7–253.3 t/year/5000 m2. From sediment cores, however, the accumulation of iron oxyhydroxide sediments on the sea floor is 39–95 t/year/5000 m2. This finding indicates that the remaining 63%–73% of iron was transported out to sea from Nagahama Bay. Even with a high rate of iron oxyhydroxide production, the sedimentation rate of iron oxyhydroxides in the bay is considerably higher than that observed in modern deep-ocean sediments. This example of rapid and abundant oxyhydroxide sedimentation might provide a modern analog for the formation of iron deposits in the geological record, such as ironstones and banded iron formations.

Much capillary electrochromatography (CEC) work is carried out on bonded silica packings which offer many advantages: the number of such packings which are available; the fact that the chemistry of bonding and the separation process are fairly well understood; and the possibility of the transfer to CEC of existing HPLC methods. Packing methods for the preparation of CEC columns have been investigated. The problems inherent in the use of burned-in frits remains an obstacle, but can be at least partially overcome by minimising the length and by silanisation. The influence of a variety of mobile phase variables on aspects of CEC is in agreement with theory for: ionic strength, organic content (including isoeluotropy), and pH. Temperature can be used as a variable to change column selectivity in CEC. The influence of pH on electroosmotic flow (EOF) by changing the degree of ionisation of residual silanol groups is similar for a wide range of neutral bonded groups, but is much less marked for bonded sulphonic acid groups. The EOF may be reversed for bonded groups containing nitrogen.