巻号一覧
25 巻, 12 号
選択された号の論文の6件中1～6を表示しています
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高杉 隆幸, 和泉 修1975 年 25 巻 12 号 p. 439-443
発行日: 1975/12/30
公開日: 2008/07/23
ジャーナル フリーThe effect of diffusion-annealing on mechanical properties was studied by tensile test on the aluminum polycrystals coated with 1.5μ thick silver- and copper-evaporated films.
The results obtained are summarized as follows.
(1) As-coated specimens with evaporated silver and copper films only show a slight increase in strength, while marked increases in both yield and flow stresses are achieved when diffusion-annealed at 450550°C for 148 hr.
(2) As the annealing temperature becomes higher, the lower maximum strength is revealed at the shorter diffusion annealing time.
(3) More pronounced effect of diffusion-annealing is observed in the specimens coated with copper than those with silver.
(4) Such surface strengthening by diffusion-annealing is related to the formation of intermetallic com-pounds which occured by the diffusion of the film into the substrate.抄録全体を表示PDF形式でダウンロード (686K) -
菅野 幹宏, 坂野 茂治, 鈴木 寿1975 年 25 巻 12 号 p. 444-450
発行日: 1975/12/30
公開日: 2008/07/23
ジャーナル フリーThe Al-4wt%Cu-Sn alloys with up to 0.064wt% Sn were solution-treated at 520°C, quenched and sub-sequently aged at temperatures ranging from 0 to 200°C. Then, the aging curves of those specimens were studied in relation to aging temperatures (TA), aging times (tA) and Sn contents, by resistivity measurements and transmission electron microscopy.
The results obtained were as follows.
(1) The shape of aging curves showed a continuous change according to TA, tA and Sn content. For instance, the aging retardation in the initial stage of aging in ternary alloys was observed. However, the transition of this retardation to acceleration seemed to occur in the latter stage of aging, more clearly with increasing Sn contents and rising TA.
(2) Transmission electron micrographs of ternary alloys aged at 100°C showed co-existence of two sorts of G. P. zones different in dimension and distribution-density, suggesting that the aging behaviors of Al-Cu-Sn alloys was related to those zones: for instance, the aging retardation would be caused by one of two sorts of zones, that is, finely and densely distributed one at low TA. However, further experiments would be needed to make clear the aging behaviors of Al-Cu-Sn alloys.抄録全体を表示PDF形式でダウンロード (1135K) -
岡本 秀仁, 浅野 和彦, 藤原 明1975 年 25 巻 12 号 p. 451-458
発行日: 1975/12/30
公開日: 2008/07/23
ジャーナル フリーLow temperature toughness of Al-Mg alloys with equi-axed grains has been investigated by means of the tear test at RT to -196°C and effects of β-precipitates on modes of fracture were discussed. The unit propagation energy (UPE) and the tear strength at -196°C decreased markedly on aging above 150°C. This was successfully attributed to the intergranular fracture as a result of precipitation of fi phase on grain boundaries. UPE was expressed as a function of the fraction of the grain boundary fracture fGB, as
UPE=-4.6fGB + 4.2, kg-mm/mm2.
It has been shown that dimple patterns are formed on the grain boundary surface after sufficient aging. The dimples were formed on β-precipitates larger than 0.1μ. When β-precipitates were smaller than 0.1μ no dimple was found on grain boundaries.
Based upon the observations, it was concluded that when β-precipitates were small (<0.1μ), ductile transgranular fracture was the main mode of fracture and when β-precipitates were large (>0.1μ), grain boundary fracture controlled the toughness of Al-Mg alloys at low temperature.抄録全体を表示PDF形式でダウンロード (1844K) -
福井 利安, 竹島 義雄, 中村 授, 馬場 義雄1975 年 25 巻 12 号 p. 459-466
発行日: 1975/12/30
公開日: 2008/07/23
ジャーナル フリーNotch toughness and fracture characteristics of Al-Mg-Zn alloys and their welds were studied by mea-suring the notched and unnotched tensile properties, Charpy impact value, crack propagation energy in a modified Navy tear test and fracture stress in a deep-notch test.
With increasing Mg content or with decreasing Zn content in the alloys with Mg+Zn≈6% (constant), ductility and toughness tended to increase, whereas strength tended to decrease. Al-4.5%Mg-1.5%Zn alloy was superior to 5083 alloy in ductility as well as strength.
Al-4%Mg-2%Zn alloy with comparable ductility to 5083 alloy was superior in strength to Al-4.5%Mg-1.5%Zn alloy, while both alloys were inferior to 5083 alloy in toughness evaluated by Charpy impact value and crack propagation energy in the tear test.
However, Al-Mg-Zn (Mg>Zn) alloy welds showed comparatively stable fracture with little reduction of fracture stress in the deep-notch test at cryogenic temperature, while the dimple pattern disappeared and intergranular cracking was observed in fractography with lowering the testing temperature.抄録全体を表示PDF形式でダウンロード (1511K) -
鈴木 寿, 菅野 幹宏, 荒木 一郎, 糸井 一博1975 年 25 巻 12 号 p. 467-474
発行日: 1975/12/30
公開日: 2008/07/23
ジャーナル フリーThe Al-4%Cu-Mg alloy specimens with 01.6%Mg were solution-treated at 505°C, quenched and subsequently aged at 100200°C. Direct quenching from 505°C to the aging temperature was also employed. The secondary defect structures in these specimens, and their influences on the precipitation of intermediate phases (particularly of S') were studied in relation to Mg contents, and aging or quenching conditions by means of transmission electron microscope.
When the specimen was quenched and aged, only dislocation loops were confirmed to develop as secondary defects; the loop size generally increased with increasing aging temperatures and Mg contents, and also by direct aging. The precipitation of S' phase was directly related to those loop structures which were varied accord-ing to Mg contents and aging conditions including direct aging. From these results, it was suggested that the precipitation of S' phase could fairly be controlled by varying the loop structure.抄録全体を表示PDF形式でダウンロード (2761K) -
宮川 松男1975 年 25 巻 12 号 p. 475-484
発行日: 1975/12/30
公開日: 2008/07/23
ジャーナル フリーPDF形式でダウンロード (1496K)
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