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1.
介绍了粉状铝基钎料的制备方法,探讨了粉状铝基钎料的工艺性能。从表面张力的角度出发,讨论了粉末粒度、氧含量、加热速度、加热均匀性、钎料钎剂比例等因素对高频铝材钎焊工艺和性能的影响。结果表明:用粒度在150~180μm的粉状铝基钎料钎焊铝材,其钎焊剪切强度较高;加热速度较快、加热盘温度均匀的钎焊效果较好;钎料钎剂的比值在10∶8~10∶10范围钎焊效果较好。 相似文献
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从钎焊工艺、钎焊料、工具产品和生产自动化4个方面介绍了当前国内外钎焊金刚石工具的研究成果,并在此基础上对钎焊金刚石工具下一步的研究重点进行了展望。详细论述了钎焊温度、保温时间、钎料合金成分对钎焊金刚石的影响。适宜的钎焊温度和保温时间可以保证金刚石/钎料界面发生充分反应,界面结合强度增强,获得较好的钎焊接头质量。添加适量的元素或化合物改进钎料合金成分,可以调控钎料的性能,降低金刚石石墨化和热损伤程度。概括总结了常规钎焊金刚石工具、磨粒有序排布钎焊金刚石工具及细粒度钎焊金刚石工具的发展现状,钎焊金刚石工具具有电镀和烧结金刚石工具无可比拟的优点;金刚石有序排布会提高工具的加工效率和使用寿命,提高磨削表面质量;对细粒度钎焊金刚石工具亟待解决的磨粒等高性和分布均匀性问题的研究进行了概述。 相似文献
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研制的ZQ—11无银高磷韧性钎料解决了高磷钎料的脆性以及不能对铁族合金钎焊的问题。在封闭式车前灯的使用中,成功地取代了HLAgCu30—25钎料。在冷气机、空调机、刀具等方面的钎焊可取代含银5%~45%的钎料。同时还探讨了材料研制和使用考核的内在机制,从而突破了钎焊手册磷铜钎料不能用于铁族合金的规定。 相似文献
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DA8501钎料是一种新型代银,节能钎料,具有熔点低,钎焊性能好和易于加工成形的综合性能,能在较宽领域内代替含银50%的银钎料,用于钢材,硬质合金,铜及铜合金等材料的钎焊,亦可代替黄铜钎料,降低钎焊温度,节约能源。 相似文献
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本文针对PDC钻头焊接的需要,研究了硬质合金真空钎焊用的Ag-Cu-In-Ti活性钎头。结果表明,在PDC热稳定极限温度以下,急冷的Ag-Cu-In-Ti钎料可以连接硬质合金,接头剪切强度可达308MPa以上。连接过程中,活性元素Ti起着重要的作用。Ti在结合界面富集并与硬质合金发生化学反应,反应的主要产物为TiC。钎焊温度和保温时间都有一个最佳范围,在此范围之内,接头强度最高。 相似文献
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Toru Nagaoka Yoshiaki Morisada Masao Fukusumi Tadashi Takemoto 《Metallurgical and Materials Transactions B》2010,41(4):864-871
To obtain sound butt-joints of 5056 aluminum alloy rods, ultrasonic-assisted soldering was conducted using Zn-18Sn and Zn-60Sn
alloys. Each solder foil was inserted between rods of 5056 aluminum alloy. Ultrasonic vibration was propagated to faying surfaces
at soldering temperatures below the liquidus temperature of the solder alloys, and then the samples were air cooled to room
temperature. The optimum vibration time at the soldering temperature must be more than 2 seconds to have complete wetting
and less than 4 seconds to avoid excessive dissolution of the 5056 alloy. The 5056 alloy joints soldered using quasi-melting.
Zn-Sn alloys showed greater strength than the joints soldered at the temperatures over its respective liquidus temperature.
As the soldering temperature was increased, the increased formation of the intermetallic compound Mg2Sn or phases containing Mg generated by dissolution of 5056 into the solder layer decreased the joint strength. Ultrasonic-assisted
soldering at an optimum temperature between solidus and liquidus of the Zn-Sn alloys is an important consideration for producing
sound joints with sufficient strength. 相似文献
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The 1996 Bigelow Award of the Boston Surgical Society: Henry Jacob Bigelow and David C. Sabiston, Jr
HB Wheeler 《Canadian Metallurgical Quarterly》1997,226(2):146-152
STATEMENT OF PROBLEM: For laboratory production, it would be economically advisable to reuse excess cobalt-chromium alloys in manufacturing partial denture frameworks. Furthermore, discrepancies in fit, modifications, repairs, and also economic factors could lead to soldering procedure on the metal framework. PURPOSE: This study evaluated the influence of soldering and remelting procedures on the fatigue strength of Steldent, Dentorium, and Biosil cobalt-chromium alloys, as new alloys and in a mixture of new and previously casted alloy and when submitted or not submitted to conventional soldering procedure. MATERIAL AND METHODS: The soldering procedure was conducted in rod specimens 1.7 mm in diameter made with new, or with a mixture of new and reused alloy (n = 10 per group). The results were compared with those of intact rods. The fatigue strength was carried out with a cyclic testing machine simulating the insertion and the removal of partial dentures. After failure, the fracture surface was examined with a scanning electron microscope. RESULTS: The soldered specimens revealed 1119 loading cycles before fracture. These means differed statistically from those of intact alloys, which disclosed 2733 cycles before failure (p < 0.05). Statistical analysis indicated that the soldering procedure reduced fatigue strength of all new alloys or those in a mixture of new and previously casted alloys. It was also found that the soldering procedure may cause premature failure of a removable partial denture. Photomicrographs from fracture surfaces revealed the presence of inclusions and voids. Conversely, there were no significant differences between new and reused specimens, soldered or not (p > 0.05), which suggested that it may be possible to reuse excess cobalt-chromium alloys without compromising the fatigue strength of the framework. 相似文献
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根据高炉开铁口钻的工作条件,选择钻头结构材料,包括钢材、硬质合金、钎料、焊剂。采用感应钎焊工艺,钻头性能满足钢铁厂开口作业要求,通过产品跟踪分析钻头报废形式,通过改进措施完善钻头设计、钎焊工艺。 相似文献
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介绍了工业炉在焊接工艺中的应用,引用设备实例对真空钎焊炉及氮基钎焊炉的原理、结构、控制方法及使用特点进行了详细描述. 相似文献
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N. N. Zagirov I. L. Konstantinov E. V. Ivanov 《Russian Journal of Non-Ferrous Metals》2012,53(2):145-149
A technology for making a welding wire with a diameter of 1.2 and 2.0 mm from the shavings of SvAK12 aluminum alloy is developed.
This technology includes hot briquetting the graded shaving scrap at 400–420°C, the hot extrusion of briquettes at 460–470°C
with elongation factors of 32 and 56, cold wire drawing the extruded bars with average unit reductions for a pass of 15–20%,
and intermediate annealings at 400°C. It is shown that this wire is suitable for soldering parts of aluminum alloys, and the
level of the mechanical properties allows it to be recommended for wide application. 相似文献
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Die soldering is one of the major casting defects during the high-pressure die casting (HPDC) process, causing dimensional
inaccuracy of the castings and increased downtimes of the HPDC machine. In this study, we analyzed actually failed core pins
to determine the mechanism of soldering and its procedures. The results show that the soldering process starts from a local
coating failure, involves a series of intermetallic phase formation from reactions between molten aluminum alloys and the
H13 steel pin, and accelerates when an aluminum-rich, face-centered cubic (fcc) phase is formed between the intermetallic
phases. It is the formation of the aluminum-rich fcc phase in the reaction region that joins the core pin with the casting,
resulting in the sticking of the casting to the core pin. When undercuts are formed on the core pin, the ejection of castings
from the die will lead to either a core pin failure or damages to the casting being ejected. 相似文献
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Tomasz Gancarz Katarzyna Berent Wojciech Skuza Katarzyna Janik 《Metallurgical and Materials Transactions A》2018,49(7):2684-2691
Magnesium has applications in the automotive and aerospace industries that can significantly contribute to greater fuel economy and environmental conservation. The Mg alloys used in the automotive industry could reduce mass by up to 70 pct, providing energy savings. However, alongside the advantages there are limitations and technological barriers to use Mg alloys. One of the advantages concerns phenomena occurring at the interface when joining materials investigated in this study, in regard to the effect of temperature and soldering time for pure Mg joints. Eutectic Zn-Al and Zn-Al alloys with 0.05 (wt pct) Li and 0.2 (wt pct) Na were used in the soldering process. The process was performed for 3, 5, and 8 minutes of contact, at temperatures of 425 °C, 450 °C, 475 °C, and 500 °C. Selected, solidified solder-substrate couples were cross-sectioned, and their interfacial microstructures were investigated by scanning electron microscopy. The experiment was designed to demonstrate the effect of time, temperature, and the addition of Li and Na on the kinetics of the dissolving Mg substrate. The addition of Li and Na to eutectic Zn-Al caused to improve mechanical properties. Higher temperatures led to reduced joint strength, which is caused by increased interfacial reaction. 相似文献
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Yu. V. Gorokhov S. V. Belyaev I. V. Uskov I. L. Konstantinov I. Yu. Gubanov T. Yu. Gorokhova P. A. Hramtsov 《Russian Journal of Non-Ferrous Metals》2017,58(1):75-79
Technical and process features of a flowsheet for fabricating the wire of casting aluminum alloys intended to solder waveguides with the use of the combined continuous casting–pressing of nonferrous metals are considered. The dependences necessary and sufficient to design the constructive elements of equipment and process modes providing the implementation of conditions for the stable run of processes of continuous supply of the metal melt into the stream of the carousel molding laboratory machine, its solidification, and extrusion into the die opening similarly to Conform technology are established. The magnitude of the cross section of the hole in the supply dispenser of the metal melt into the stream of the crystallizer wheel is calculated. The process modes of the continuous casting–pressing using a laboratory installation of a billet 3 mm in diameter and its subsequent treatment by high-quality rolling and drawing in combination with intermediate annealing procedures to the final sizes are presented. According to this flowsheet, a pilot batch of round and square wire of alloys AK12Ts10 and AK12Ts15 has been produced in the amount of 3 kg and delivered to the AO ISS enterprise for industrial test soldering of waveguides. 相似文献
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Vineet Kumar Zhigang Zak Fang Jin Liang Nader Dariavach 《Metallurgical and Materials Transactions A》2006,37(8):2505-2514
Among the many issues related to the performance of lead-free solder alloys, the dependence of their mechanical properties
on the microstructure and the stability of the microstructure stability are some of the most important issues. A comprehensive
understanding of the process-microstructure-property relationships is essential. Toward that goal, a microtextural analysis
is performed using orientation imaging microscopy (OIM) for alloy Sn-3.8Ag-0.7Cu (wt pct) processed at four different temperatures.
Sn-3.8Ag-0.7Cu is one of the most promising lead-free solder alloys that has shown superior mechanical properties to other
candidate lead-free solder alloys. However, a comprehensive understanding of their microstructure and the dependence of microstructure
on processing conditions are still lacking. In the present work, a detailed microstructure characterization with respect to
phase compositions, grain size and size distributions, texture, and orientation relationships between various phases are performed.
The measured microstructural features are correlated with the soldering temperatures. 相似文献
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Metallurgical, mechanical, and environmental factors all affect service reliability of lead-free solder joints and are under
extensive study for preparation of the transition from Sn-Pb eutectic soldering to lead-free soldering in the electronic industry.
However, there is a general lack of understanding about the effects of solidification conditions on the microstructures and
mechanical behavior of lead-free solder alloys, particularly on the long-term reliability. This study attempts to examine
the creep resistance of the Sn-Ag-Cu eutectic alloy (Sn-3.8Ag-0.7Cu, SAC387) with a variety of solidification conditions with
cooling rates ranging from 0.3 °C/s to 17 °C/s. Results indicate that solidification conditions have a major influence on
the creep resistance of SAC387 alloy; up to two orders of magnitude change in the steady-state creep rates were observed at
low stress levels. An understanding of the mechanical property change with microstructures, which are determined by the solidification
conditions, should shed some light on the fundamental deformation and fracture mechanisms of lead-free solder alloys and can
provide valuable information for long-term reliability assessment of lead-free solder interconnections.
This article is based on a presentation made in the symposium entitled “Solidification Modeling and Microstructure Formation:
in Honor of Prof. John Hunt,” which occurred March 13–15, 2006 during the TMS Spring Meeting in San Antonio, Texas, under
the auspices of the TMS Materials Processing and Manufacturing Division, Solidification Committee. 相似文献