The influence of 28 element additions on the melting point, flowability, corrosion resistance and fillet bending ability of A1-Si type filler metal has been investigated. Among these systems, filler 6M, i. e.A1-Si(13.0)-Be(0.4—0.8)-Sr (0.03—0.06)-La (0.03—0.06) is regarded as the optimum. The erosion mechanism of molten filler metal on base metal has been also studied. In addition to the influences of brazing temperature and the composition of filler metal, the rate of solution of base metal into molten fil...             考察了28种有代表性的微量元素对Al-Si共晶钎料的熔点,流动性,抗腐蚀性以及钎缝折弯能力的影响。其中以Al-Si(13.0)-Be(0.4—0.8)-Sr(0.03—0.06)-La(0.03—0.06)钎料体系最为理想。本文还探讨了钎料对母材熔蚀的机理,分析了钎焊温度和钎料组成的影响,此外,还认为与母材熔入钎料的速度以及液态钎料沿钎缝的流布速度有关,此二速度的比值愈大,熔蚀愈烈。最后,在钎焊温度下对钎缝进行了不同时间的保温处理,发现钎缝的强度和抗弯能力仅有不大程度的改善。 文摘来源          This paper deals with histological changes in the muscle of some commercial fishes during freezing and frozen storage.The experiments were carried out under various conditions, namely, freezing at different temperatures and rates, frozen storage at different temperatures, freezing and frozen storage by using fishes iced for various periods prior to freezing and fishes with different oil contents subjecting to tests. The results obtained are as follows: 1. When fish is frozen at low temperature, the water in...             几种经济鱼类在冷冻冷藏中组织学变化的研究,得到了以下结果: 1.鱼肉在低温下冷冻时,肌肉纤维的水发生内冻结,冰晶体小,可以较好地保持其组织结构的完整。考虑到冻鱼在冷藏中仍继续变化,采用-25°——35℃温度冷冻鱼品是适宜的。 2.快速冷冻可使鱼肉组织不受冰晶体的破坏。梭鱼片在104分钟以内的不同速度 (鱼肉中心温度由0°至-5℃所需的时间)冷冻的结果均较好,其中以27、40、72分钟者更能令人满意。试验表明,鱼肉的冷冻速度不是愈快愈好。鲵鱼片用60—1,500分钟八种速度单向冷冻时,除720、1,380和1,500分钟的较差外,其他速度冷冻的肌肉组织相似。 3.冰藏1、7和13天的小黄鱼在相同温度下冷冻后,肌肉组织结构有差异,冰藏了天以上者差异特别明显。三种冰藏期的冻鱼以相同温度冷藏时,冰藏13天后的冻鱼,其保藏期较前二种冰藏期的短2—3个月。 4.冻鱼的冷藏温度十分重要。用相同的和低于冷冻时的温度保藏鱼类,可以较好地保持肌肉组织不受破坏。在-18℃冷冻并冷藏和-10℃冷冻后、-18℃冷藏的大黄鱼的保藏期,较之在-29℃(鼓风)冷冻后分别在-18°和-10℃冷藏的延长1—2个月。 5.不同含脂量的鱼(小黄鱼、... 文摘来源          A study has been made of the effects of twenty metal additions in small amount on the corrosion resistance in 3% NaCl solution of Al-Zn euteetic fillets on pure aluminum as well as on LY12 (2024) base metals as determined by weight loss and by metallographic technique. It is shown that corrosion resistance effectively increses with the addition of small amounts of alkaline earth and rare earth elements, such as Be, Mg, Sr and La. The addition of heavy metals, such as Bi, Sn, Pb, Cd, Tl, Cu, Ni and Ga ...             用经典失重法和显微结构法研究了20个少量添加元素对纯铝及LY-12母材上Al-Zn钎料焊点抗腐蚀性能的影响。发现添加少量碱土金属或稀土金属能有效地提高焊点的抗腐蚀性。少量重金属Bi,Sn,Pb,Cd,Tl,Cu,Ni及Ga等引起合金强烈的晶间腐蚀。过渡金属及碱金属影响不大。 文摘来源          It was shown from experimental results that excellent brazability of aluminiumalloy could be obtained with magnesium activator in vacuum brazing.It was thepurpose of the present study with the help of Auger electron spectroscopy and Scanningelectron microscopy surface analysis to research for variation of magnesium constituentand surface configuration of brazing filler metal layer on composite sheet specimens.At different temperature the concentrated evaporation of magnesium constituent atmelting temperatur...             试验证明,铝真空钎焊时,大都借助于镁才能获得优质接头。本文研究了复合板试样经不同温度的钎焊加热后,用俄歇能谱仪及扫描电镜分析钎料层中镁的变化及钎料层表面形态的变化,明确了镁在钎科熔化温度下能产生聚集性蒸发。这一现象对形成优质接头具有重要作用。此外,用附加镁块的方式,研究了不同镁蒸气浓度对钎料填充间隙能力的影响。结果表明,钎缝附近镁的浓度适量是获得优质钎缝的关键。浓度过大,钎料流失;浓度过小,钎料不漫流,均形不成焊角。通过环状的T 型接头试验,由于结构开敞程度的不同(如内外焊角),镁蒸气的作用效果亦不同,调整附加镁量或加罩可获得优质接头。在上述试验的基础上,应用试验所得结果及工艺措施,成功地钎焊了具有空间曲面T 型接头的叶轮。 文摘来源          To study the effect of candling fish fillets electronically by measuring the voltage output of a photomaltiplier tube produced from diffused light beam impinging upon fish bones with the following Variables:1. two fillet thicknesses, 6.35mm and 12.70mm:2. two equivalent processing belt speeds, 0.1m/s and 0.2m/s;3. three eguivalent belt speeds, for at least one bone of each of four di mensions from one fish;4. four different wavelengths as produced by Colored "Polythane" filme of red, blue, green and t...             本试验是用测量光电倍增管输出电压的电子学方法,研究白热光照射带骨鱼块的检骨效果。这些输出电压是在不同的试验条件下漫射光束照射在鱼骨上产生的,其不同的试验条件如下: 1.二种鱼块厚度为6.35亳米和12.70毫米; 2.二种对应的运输机皮带的速度为0.1米/秒和0.2米/秒; 3.从鱼块中挑选出四种不同厚度的鱼骨,即0.254亳米,0.381亳米,0.508亳米,0.635亳米。取其中之一的鱼骨,在三种皮带速度条件下,即0.10米/秒,0.20米/秒,0.40米/秒,重复三次试验; 4.用四种不同波长的光束,即480亳微米,530亳微米,650亳微米和白热光,对四种鱼骨中每一种依次进行试验。 文摘来源          The metallurgical process of the fillets formed during aluminum brazing has been discussed. The dissolve of base-metal into the liquid fillet metal was first beginning at its crystal boundaries, owing to the homogenization of the liquid phase, Si permeates into the boundaries. Meanwhile, Si in the liquid diffused into Al granules, thus the a-phase formed.             讨论了钎焊温度下铝钎焊钎缝的冶金过程:1.Al母材溶入钎料首先从晶界处开始,由于液态钎料的均匀化,Si渗入了晶界;2.液态钎料中的Si向母材Al晶粒中扩散形成α相。 文摘来源          It is known that fatiguefracture is the main form of failure occurring to a sucker rod. It is necessary to conduct an investigation on the shape in designing a sucker rod. The author performed several experiments. Firstly, by means of photoelastic experiment, he made a comparison between both 7/8" sucker rods of JB2823-79 and API Specification. Secondly, the author analysed the surface stress distribution state at the upper forged portions of two 7/8" sucker rods in different structural forms through simula...             抽油杆主要失效形式是疲劳断裂,因此,必须对抽油杆的结构形状进行研究。作者用光弹性试验,对JB2823-79和API两种规范的7/8＂抽油杆进行了对比,通过两种结构形式的7/8＂抽油杆模拟试验,分析了杆头锻造部分的表面应力分布情况;对5/8＂、3/4＂、7/8＂、1＂和9/8＂五种抽油杆进行了平面光弹试验,分析了扳手方附近的过渡圆角的大小对该部位应力分布的影响;最后又通过四种不同卸荷槽长度的模型试验,分析了卸荷槽长度对公螺纹各牙受载情况的影响。 文摘来源          For design optimization of the meshing parameters of reducer gears on sucker rod pumping units, the author presents the implication and formula of the flank contact strength of helical gears· Relevant factors, as the effectiveness of face width and the transverse contact ratio, are taken into consideration,in order to tally with the actual stress on the tooth faces and combine structural design with theory of material strength more closely· In addition,design factors for stress concentration caused by key s...             本文针对抽油机减速器齿轮啮合参数的优化设计,提出了斜齿轮齿面接触强度的定义和计算公式。计算中考虑了齿宽有效度、端面重合度和附加重合度因素,以期更符合齿面实际受力情况,使机械设计与材料强度理论结合得更好。还对有关轴的键槽、轴孔、轴肩所引起的应力集中系数的计算方法作了补充。 文摘来源          The investigation into fractured surfaces of the connecting rods in diesel engines as well as the results of static stress test and model fatigue test of the rods are presented in this paper. It is revealed that the causes of fracture of these connecting rods include: 1. stress concentration at shoulder fillets, 2.less structural strength, and 3. surface decarbonization and unsufficient shot peening.             《石油机械》第14卷第7期,1986,第10～17页,图12,表5 本文作者对柴油机连杆断口进行了观察分析,并对连杆进行了静态应力测试和实物模拟疲劳试验。分析结果说明,连杆断裂的原因主要是:1.工艺凸台圆角处应力集中;2.结构强度不足;3.表面脱碳及喷丸强化不够。 文摘来源          Existing algorithms for generating fillet of planar or quadric surfaces can not be applied to free-form surfaces. In this paper, free-form surfaces are represented by bicubic Bener patches. Recursive algorithm using the principle of subdivision is used to find the intersection of Bener surfaces. Then, the algorithm for generating fillets around the intersection is presented and implemented. The fillet surfaces are also represented by bicubic Bener surfaces. The program of this algorithm is written in...             现有的为平面或二次曲面产生过渡曲面的算法均不能用于自由曲面。本文用双三次 Ｂｅｚｉｅｒ曲面片来表示自由曲面，用基于分割的递归算法求出自由曲面之间的交线，在这 基础上，提出并实现了围绕交线产生过渡曲面的算法，过渡曲面本身也是用双三次Ｂｅｚｉｅｒ 曲面来表示的。所述算法已在ＤＯＲＡＤＯ计算机上用ＣＥＤＡＲ语言实现，并作了实例计 算。 文摘来源

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