复层固液分离膜的制备及性能研究

采用聚丙烯（PP）粉末在非织造布表面烧结的方式来制备多孔质复层固液分离膜,并通过粘合剂及烧结时间2个变量来控制分离膜的孔径、渗透率等性能。结果表明：随着粘合剂的增加,分离膜的渗透性能下降明显,孔径变小;同时热压时间的延长也会影响分离膜各项性能,但比粘合剂影响小。     

羟基磷灰石生物陶瓷的成型研究

在适宜的条件下，用化学沉淀法合成羟基磷灰石，加以不同粘合剂，并通过干压使其成型，控制不同温度将其烧结成陶瓷。简单分析烧结温度、时间及粘合剂等对HAP陶瓷成型的影响。结果表明：1100℃和3h是HAP生物陶瓷较佳的烧结温度和烧结恒温时间；比较之下，聚乙烯醇对HAP的干压成型工艺较适宜。     

石英长石分选尾砂陶瓷砖

以石英长石分选尾砂为基 ,并配以与其颗粒具有矿物相容性的易熔粘合剂研制成了各种陶瓷砖。确定了粘合剂的组成和含量、尾砂的粒度组成和煅烧温度对瓷砖生产用复合材料烧结的影响     

石英长石分选层砂陶瓷砖

以石英长石分选尾砂为基,并配以与其颗粒具有矿物相容性的易熔粘合剂研制成了各种陶瓷砖。确定了粘合剂的组成和含量、尾砂的粒度组成和煅烧温度对瓷砖生产用复合材料烧结的影响。     

低温共烧多层陶瓷基板烧结收缩控制技术

低温共烧多层陶瓷基板烧结收缩率的控制很重要,本文通过控制粉料粒度、流延粘合剂比例、热压叠片压力和烧结曲线等,可将收缩率控制在14％±0.4％内。     

污泥和石英尾矿制备建材陶粒的烧结温度研究

为了处理城市污水处理厂的污泥,将污泥配以石英砂尾矿、粘合剂和河道底泥添加剂可以生产轻质陶粒。利用脱水污泥,经过粉磨、干燥、焙烧等加工工艺,按照陶粒原料组成以污泥∶石英砂尾矿∶粘结剂∶河道底泥=4∶4∶3∶3、进料温度为400℃、预热时间为20 min、烧结时间为25 min为条件,考察烧结温度对陶粒性能的影响,结果表明,烧结温度为1 080℃时,陶粒的筒压强度最大、吸水率和堆积密度最小。     

涂料印花粘合剂概述

一、前言涂料印花粘合剂是涂料印花浆的主要成份,各种染料或颜料靠粘合剂成膜使其粘盖在织物上,从而达到着色印花之目的。涂料印花所用的颜料主要是分散染料,也可用萤光颜料、金粉、银粉等颜料。所用粘合剂从无机到有机物质,从低分子到高分子物质,其发展历史是比较悠久的。特别是七十年代出现的可以交联的粘合剂,如丙烯酸酯共聚乳液(单体中加入了自交联单体)粘合剂问世以后,涂料印花粘合剂的发展更为迅速。它在印染行业中占有极其重要的地位。本文结合科研工作,将国内外涂料印花粘合剂的发展、合成和应用情况,作一简要介绍。     

汉高高性能粘合剂在汽车工业应用广泛

汉高(Henkel)是粘合剂、密封剂和表面处理解决方案的全球市场翘楚,其所提供的技术几乎应用于汽车开发的所有阶段。该公司的产品不仅用于车身喷漆前处理,还成功应用于汽车的保养和维修。汽车业正在越来越多地使用高性能粘合剂来粘结不同的零部件。使用粘合剂进行粘结可以使车辆更加轻盈、安静、耐用和安全。粘合剂在汽车业的应用之广泛堪比粘合剂技术本身。粘合剂粘结正在日益取代传统的连接技术,例如焊接、铆接或螺栓连接。这不仅能提升安全性,还能简化很多生产作业,从而提升汽车的成本效益。在汽车制造的每个阶段,不管是非承重车     

用注射成型法铸造金属制件

德国BASF公司不久前正式推广一项新技术———用普通注射成型机铸造金属制件或氧化物陶瓷制件。该技术系利用一种含有专用催化剂的酯类粘合剂 ,先将金属粉末或氧化物粉末在该粘合剂的作用下粘结并挤出造粒 ,再将粒料经注射成型为制件的生坯。生坯被置于 110～ 14 0℃的烘炉中2～ 3小时 ,由于粘合剂在该温度下被催化剂引发分解 ,生坯即成为制件的毛坯。毛坯再经高温烧结、冷却并抛光 ,即得制件成品。该技术的核心是带有催化剂的酯类粘合剂 ,BASF已在多个国家取得了专利。其优势在于粘合剂分解时由外渐进到内 ,不会引起一般粘结剂 (如石蜡…     

喷墨相纸中PVA粘合剂与打印性能的关系

本文研究了彩色喷墨打印相纸的粘合剂与性能的关系。讨论了PVA粘合剂的聚合度对相纸性能以及PVA粘合剂用量对吸墨性能的影响。结果显示,粘合剂聚合度大有利于相纸性能的提高,粘合剂用量对相纸吸墨性能影响较大,合适的PVA聚合度和用量可以得到各项性能优良的喷墨打印相纸。     

Effects of Ni addition on properties of vitrified bond CBN composites in strong magnetic field

Properties of vitrified bond with varying Ni doping amounts were extensively investigated. Effects of Ni addition on microstructures and properties of vitrified bond cubic boron nitride (CBN) composites prepared in strong magnetic field were investigated for applications in CBN grinding tools. Vitrified bond was characterized using three-point bending, scanning electron microscopy, X-ray diffraction and other methods. The refractoriness, fluidity, and bending strength of vitrified bond were evaluated. Bending strengths, microstructures, and phase compositions of vitrified bond CBN composites achieved using conventional and strong electromagnetic sintering techniques were compared. Results show that the addition of Ni to vitrified bond CBN composites improved the fluidity and bending strength of the vitrified bond. Strong electromagnetic sintering improved the mechanical strength and pore structure of vitrified bond CBN composites. Moreover, the introduction of the strong magnetic field facilitated Ni migration and aggregation in vitrified bond, rotated abrasives, and formed new substances, thus increasing the stability of vitrified bond CBN composite thermal material. Also, strong magnetic field inhibit grain growth of non-magnetic and ferromagnetic materials with fine-grain effect.     

金属铝粉和纳米Al2O3粉对陶瓷结合剂性能的影响

将金属铝粉、纳米Al₂O₃粉引入基础陶瓷结合剂,通过红外光谱分析陶瓷结合剂玻璃结构,X射线衍射表征其物相变化,并测试其耐火度,利用扫描电镜分析陶瓷结合剂立方氮化硼(CBN)复合材料的微观结构,并测试抗折强度,系统分析了金属铝粉、纳米Al₂O₃粉的单掺及复掺对陶瓷结合剂性能的影响。结果表明,金属铝粉使陶瓷结合剂耐火度升高,玻璃结构没有明显改变,部分铝粉转变为Al₂O₃,添加金属铝粉的陶瓷结合剂CBN复合材料抗折强度随烧结温度升高而提高。纳米Al₂O₃粉使陶瓷结合剂耐火度降低,呈玻璃相,但有少量Al₂SiO₅晶体和Li_xAl_xSi_3-xO₆晶体析出,添加纳米Al₂O₃粉的陶瓷结合剂CBN复合材料烧结温度720 ℃时出现较高抗折强度,达93.7 MPa。金属铝粉和纳米Al₂O₃粉的复掺有利于玻璃网络结构的键合,陶瓷结合剂以玻璃相为主,也有少量晶体析出,二者复掺对提高陶瓷结合剂CBN复合材料抗折强度更有优势,但烧结温度也相应升高,烧结温度740 ℃时抗折强度达最高值,为97.4 MPa。     

Effects of sintering in a high magnetic field on properties of vitrified bond and vitrified CBN composites

Vitrified bond CBN grinding wheels are being widely used due to their superior performance. Also, advantages of vitrified grinding wheels are high elastic modulus, stable chemical property, and low thermal expansion coefficient. Brittleness and low strength are key factors restricting the development of vitrified bond CBN grinding wheels. In this paper, the sintering in a high magnetic field was innovatively introduced into the manufacturing of vitrified bond CBN grinding wheels, and the effects of sintering in a high magnetic field on properties on vitrified bond and vitrified CBN composites were systematically investigated. Vitrified bond was characterized using three-point bending, scanning electron microscopy, X-ray diffraction. It was observed that microstructure of vitrified bond could be changed, grain orientation could be controlled and average grain size could be decreased in a high magnetic field, while vitrified bond strength could be simultaneously improved. High quality vitrified bond could be obtained by appropriately adjusting the strength and direction of high magnetic field. Results demonstrated that vitrified bond properties were improved when the magnetic field strength was 6?T. In order to highlight the high magnetic field effect on the vitrified CBN composites, the ordinary CBN abrasives and nickel plated CBN abrasives were used respectively. Microstructures, bending strengths of vitrified CBN composites were compared in different high magnetic fields. When the magnetic field strength was appropriate (less than 6?T), the binding characteristic of vitrified bond CBN composites with nickel plated CBN abrasives was greatly improved. The highest bending strength value of vitrified CBN composites was 79.5?MPa in 6?T high magnetic field.     

Effect of TiO2 addition and high magnetic field sintering on properties of vitrified bond CBN composites

Vitrified bond CBN composites, with different amounts of TiO₂ doping, were prepared by conventional sintering and high magnetic field sintering processes. Mechanical properties, cross-sectional morphology, refractoriness, fluidity and structural characterization have been carried out to understand the role of TiO₂ addition and sintering conditions. Results show that TiO₂ addition significantly affected bending strength, refractoriness and fluidity of vitrified bonds. In addition, high magnetic field sintering improved bending strength and the microstructure of vitrified bond CBN composites. Due to high magnetic field sintering, CBN grains were completely covered by vitrified bond and exhibited fewer pores. In addition, high magnetic field promoted the growth of specific grains, such as SiO₂, whereas suppressed grain growth of other crystal phases, such as NaAlSi₃O₈.     

Sintering,microstructure, and mechanical properties of vitrified bond diamond composite

The demand for high-performance grinding wheels is gradually increasing due to rapid industrial development. Vitrified bond diamond composite is a versatile material for grinding wheels used in the backside grinding step of Si wafer production. However, the properties of the vitrified bond diamond composite are controlled by the characteristics of the diamond particles, the vitrified bond, and pores and are very complicated. The main objective of this study was to investigate the effects of SiO₂–Na₂O–B₂O₃–Al₂O₃–Li₂O–K₂O–CaO–MgO–ZrO₂–TiO₂–Bi₂O₃ glass powder on the sintering, microstructure, and mechanical properties of the vitrified bond diamond composite. The elemental distributions of the composite were analyzed using electron probe micro-analysis (EPMA) to clarify the diffusion behaviors of various elements during sintering.The results showed that the relative density and transverse rupture strength of the composite sintered at 620 °C were 91.7% and 126 MPa, respectively. After sintering at 680 °C, the glass powder used in this study exhibited a superior forming ability without an additional pore foaming agent. The relative density and transverse rupture strength of the composite decreased to 48.2% and 49 MPa, respectively. Moreover, the low sintering temperature of this glass powder protected the diamond particles from graphitization during sintering, as determined by X-ray diffraction and Raman spectrum. Furthermore, the EPMA results indicate that Na diffused and segregated at the interface between the diamond particles and vitrified bond, contributing to the improved bonding. The diamond particles can remain effectively bonded by the vitrified bond even after fracture.     

添加剂对CBN高速砂轮用低温烧结陶瓷结合剂强度的影响

采用正交实验方法研究了MgO、P2O5、CaCO3、ZnO四种添加剂对陶瓷结合剂强度的影响,通过扫描电镜,分析了添加这四种添加剂的陶瓷结合剂的微观结构.结果表明:四种添加剂对陶瓷结合剂强度的影响从大到小依次是MgO≥ZnO＞ CaCO3≥P2O5;试样随着烧结温度的升高,气孔数量明显增加,形状规则,呈圆形,且气孔表面光滑,分布均匀.     

碱金属氧化物Na2 O对陶瓷结合剂金刚石磨具性能的影响

通过调整陶瓷结合剂中碱金属氧化物Na2 O含量,来探究碱金属氧化物Na2 O对陶瓷结合剂金刚石磨具性能的影响.当n(Na2O)/n(SiO2)=0.1时,磨具试样的强度(57.7 MPa)和硬度(117 HRB)达到最大值.随着碱金属氧化物Na2 O添加量的增加,结合剂的耐火度随之显著降低,流动性显著增加.磨具试样断口...     

Influence of holding time on the interfacial solid solution and mechanical properties of agglomerated white fused alumina abrasives

In this paper, the aging relationship between holding time and the interfacial solid solution was utilized to prepare high-performance agglomerated white fused alumina (AWA) abrasives. The influence of holding time on the interfacial solid solution and mechanical properties of AWA abrasives were systematically investigated, and the grinding performance was thoroughly analyzed. The results showed that increasing the holding time caused the Al₂O₃ to violently infiltrate the interface between the white fused alumina (WA) particles and the vitrified bond, which led to the precipitation of a large amount of β-spodumene and monoclinic celsian in the vitrified bond and transformed the simple mechanical bonds between the WA particles and the vitrified bond into stronger chemical bonds. Thus, it was possible to control the mechanical properties of the AWA abrasives by adjusting the holding time. Specifically, after sintering at 760 °C for 4h, the single particle compressive strength and impact toughness reached the maximum values of 26 N and 63%, respectively. In comparison with the WA grinding wheel, the grinding ratio of the AWA grinding wheel was increased by 17.9% and the workpiece surface roughness was reduced by 21.1%.     

Influence of TiO2 amount on the interfacial wettability and relevant properties of vitrified bond CBN composites

The influence of TiO₂ amount on the microstructure and relevant properties of SiO₂-Al₂O₃-B₂O₃-Na₂O-Li₂O-BaO vitrified bond and vitrified bond CBN composites were systematically studied via SEM, EDS, FTIR, and XPS. Results indicated that adding TiO₂ could regulate the quantity of β-quartz solid solution and rutile crystals in the vitrified bond and considerably affect the thermal properties and mechanical strength of this bond. Under sintering temperature, the dense B₂O₃ oxide layer on the CBN surface diffused into vitrified bond and reacted with Ti⁴⁺ enriched at the interface to form a strong chemical Ti-B bond. This reaction extensively improved the interfacial wettability between the CBN and the vitrified bond. When the TiO₂ amount was 6wt.%, the interfacial wettability significantly improved, and the wetting angle decreased from 68° to 43°. The flexure strength and hardness of the composites were 116.18 MPa and 128 HRB, which were 48.49% and 34.74% higher than those of the basic-formula composites, respectively.     

Variations in structure and properties of vitrified bonds and vitrified diamond composites prepared by sol-gel and melting methods at different sintering temperature

Differences in structure and properties of Na₂O–Al₂O₃–B₂O₃–SiO₂ vitrified bonds and vitrified diamond composites prepared by sol-gel and melting methods were methodically discussed. Results showed that the vitrified bond prepared by sol-gel method contained more [AlO₄] tetrahedron and owned higher bending strength, with the maximum value reaching 137 MPa, 31.73% higher than that prepared by melting method (104 MPa). As the sintered temperature rose, coefficient of thermal expansion of the vitrified bond prepared by sol-gel method increased first and then decreased, acquiring a maximum value of 5.75 × 10⁻⁶ °C ⁻¹ at 720 °C, which was still much lower than the minimum value of vitrified bond prepared by melting method (7.02 × 10⁻⁶ °C ⁻¹). The vitrified diamond composite prepared by sol-gel method possessed lower sintering shrinkage than that prepared by melting method, and could be applicable to the production of grinding tools with high dimensional accuracy. What's more, the maximum bending strength of vitrified diamond composites obtained by sol-gel method was 106 MPa, 24.7% higher than that of vitrified diamond composites prepared by melting method (85 MPa).