氧化铁和发泡剂对煤矸石闭孔发泡陶瓷的性能影响

以固体废弃物煤矸石为主要原料,采用粉料坯体发泡法制备闭孔发泡陶瓷,探讨了氧化铁和发泡剂掺量对发泡陶瓷性能的影响。结果表明:氧化铁掺量对发泡陶瓷容重、抗压强度和导热系数影响较大;发泡剂掺量对发泡陶瓷孔径大小、孔的均一性具有显著影响。在外加6 wt%氧化铁的前提下,发泡剂掺量为1.8~2.0 wt%时,可烧制出容重较低,孔径大小适中,保温隔热性能较好的发泡陶瓷。最终以煤矸石掺量为60 wt%的坯料烧结出容重为170~270 kg/m3,抗压强度为1.24~3.71 MPa,导热系数为0.06~0.09 W/(m·k)的发泡陶瓷。     

烧成温度和发泡剂对粉煤灰泡沫陶瓷的性能影响

以粉煤灰、废陶瓷和山皮土为主要原料,SiC为发泡剂,采用原位发泡法制备泡沫陶瓷,考察了SiC掺量、烧成温度对材料孔隙率、体密度和抗压强度的影响。结果表明,当烧成温度为1300～1400℃,发泡剂SiC掺量以4～6wt%时,可制备出孔隙率高、体密度低、孔径均匀的泡沫陶瓷。     

发泡剂在泡沫玻璃中的应用

泡沫玻璃是一种新型的保温隔热多孔材料,发泡剂是促进配合料产生泡沫从而形成气孔结构的物质,对泡沫玻璃的孔径、孔分布等孔结构有着直接影响.介绍了不同发泡剂的发泡机理及选择方法;评述了发泡剂的种类、掺量和细度对泡沫玻璃孔结构及其性能的影响;讨论了发泡剂种类、掺量及细度的选择与控制原则.     

动物蛋白发泡剂制备泡沫混凝土的研究

制备了一种动物蛋白发泡剂,并用其进行泡沫混凝土实验.本文采用表面活性剂发泡与矿物材料发泡相结合的新型模式.探讨了水灰比、粉煤灰、泡沫量以及矿物材料掺量对泡沫混凝土的影响,确定了各组分的最佳掺量.在此条件下制得了一系列泡沫混凝土砌块,其容重为581～772 kg/m3,抗压强度为3.0～6.0 MPa,吸水率为19%～28%.     

花岗岩锯泥和大理石废石粉制备发泡陶瓷

为实现“双碳”目标，推动大宗固废的资源化利用，开发探究多种固废协同制备发泡陶瓷材料的方法理论，以花岗岩锯泥和大理石废石粉为主要原料，SiC为发泡剂，通过高温烧结制备高闭气孔率的发泡陶瓷，研究原材料配比、烧结温度以及发泡剂掺量对发泡陶瓷的孔结构及性能的影响。结果表明，大理石废石粉中的CaCO₃在高温下分解出的CaO是有效的助熔剂，能够破坏Si—O键，降低液相的黏度，促进发泡。同时CaO能够与SiO₂反应生成硅灰石，提高材料的机械强度。在烧结温度为1 130℃、大理石废石粉质量掺量为10%、SiC质量掺量为1.0%时，制备的发泡陶瓷孔结构均匀，综合性能最佳，闭口气孔率为79.16%,体积密度为583.42 kg/m³,抗压强度为3.86 MPa,吸水率为0.40%。本研究为花岗岩锯泥和大理石废石粉回收利用制备发泡陶瓷提供了理论基础。     

水泥基发泡保温材料的制备工艺与性能研究

以普通硅酸盐水泥(P.O42.5)为主要胶凝材料,采用物理发泡工艺制备发泡水泥节能保温材料,发泡剂分别采用动物复合泡沫剂、植物改性泡沫剂和植物泡沫剂干粉,研究了发泡剂种类、水灰比和玻璃纤维掺量对水泥基发泡保温材料性能的影响,确定了水泥基发泡保温材料的最佳配合比.实验结果表明:发泡剂选择植物改性泡沫剂,水灰比为0.5,玻璃纤维掺量为1.5％时,水泥基发泡保温材料的干密度为356 kg/m3,7d抗压强度可达1.71 MPa.     

高掺量工业废渣建筑陶瓷锦砖的研制

研究了利用粉煤灰和铬渣的已有组分,分别以超过65%的粉煤灰、铬渣与15%左右的粘土、20%左右的长石,在1220～1240℃烧结,获得吸水率为0.3%以下,性能优于国家标准（GB/T 4100-2006）的两种高掺量工业废渣建筑陶瓷锦砖。针对坯料球磨后的泥浆悬浮性不好,坯料成型性能较差的现象,采用添加羧甲基纤维素钠（CMC）提高高掺量工业废渣砖坯泥流变性和成型性能,以达到成型工艺的要求。既为制备陶瓷所需的天然原料找到了替代品,又实现了对工业废渣的资源化,减量化,无害化处理。     

高温发泡法制备粉煤灰隔热耐火砖

以高铝粉煤灰为主要原料,高碳铬铁合金渣为辅助原料,采用高温发泡法制备出一种新型粉煤灰隔热耐火砖,并系统研究了助熔剂掺量、辅助原料掺量以及发泡剂种类等对隔热耐火砖性能的影响.结果表明:借助于高温发泡法,所制备出的隔热耐火砖,其体积密度≤500kg·m-3、常温抗压强度≥6MPa、1250℃下加热永久线变化≤2％,是一种轻质高强且低导热的隔热耐火材料.     

发泡混凝土的影响因素分析

发泡混凝土是以水泥为主要胶凝材料,基于双氧水发泡工艺制成的一类轻质多孔的保温材料。试验研究水温、粉煤灰掺量、稳泡剂掺量和发泡剂掺量四个因素分别对发泡混凝土制备的影响。结果表明:适宜制备工艺的搅拌水温为32℃左右;粉煤灰的最佳掺量为胶凝材料总量的40%;稳泡剂掺量为1%;基于成本、发泡效果以及试块的成型效果,发泡剂掺量为3%和3.5%。     

镍渣基泡沫玻璃的制备及其性能研究

以镍渣和废玻璃作为主要原料,使用Na2CO3为发泡剂,采用模具装填法来烧制泡沫玻璃.研究了镍渣的掺量、发泡剂掺量、发泡温度和发泡时间对泡沫玻璃的气孔结构和相关力学性能的影响.研究表明:镍渣掺量减少,Na2CO3掺量增加和发泡温度的升高,均会降低泡沫玻璃的体积密度,提高样品的平均气孔直径;镍渣掺量对泡沫玻璃的组成成分和晶体种类没有明显的影响;以20%镍渣和80%玻璃粉为主料,5%~7%Na2CO3为发泡剂,在发泡温度870 ℃下保温60 min,可以制备出气孔率为85.14%,体积密度为0.3715 g/cm3,抗折强度为2.062 MPa,平均气孔直径在3.13 mm的镍渣基泡沫玻璃.     

Preparation of foamed ceramics from steel slag with high calcium and iron content

In this paper, steel slag foamed ceramics were fabricated by using steel slag, kaolin, feldspar, and quartz as main raw materials, and adding SiC as high-temperature foaming agent. The effects of steel slag content and SiC particle size on porosity and mechanical properties of foamed ceramics were researched. Results indicate that when content of steel slag is 40 wt%, and particle size of SiC is 20 µm, foamed ceramics exhibited optimized properties: water absorption rate of 2.59%, total porosity of 55.91%, bulk density of 1.33 g·cm⁻³, and compressive strength of 1.21 MPa. The results show that with the increase of steel slag content, the phase composition of foamed ceramics changes, and foam process is hindered. The increase of steel slag content contributes to the formation of diopside. Fe³⁺, Fe²⁺ in liquid phase enter into diopside by solid solution, the amount of liquid phase decreases. Liquid phase mass transfer slows down, and content of SiC in liquid phase decreases, so that the porosity decreases. At the same steel slag content, different SiC particle size affects the difference between pressure inside the closed pore and surface pressure, thereby the porosity changes.     

抛光渣体系发泡陶瓷的发泡性能研究

以工业上成熟的抛光渣体系配方制备发泡陶瓷,探讨了烧结温度对其发泡性能的影响。同时,与外加发泡剂的抛光渣体系发泡陶瓷试样的显微结构、线收缩和体积膨胀率进行了对比分析,探讨了孔结构对发泡陶瓷试样强度和热稳定性的影响。研究发现,抛光渣具备一定的发泡能力,自身可发泡形成尺寸为10~200 μm(1 160~1 220 ℃)的球形气孔结构,孔壁的结构较致密。其对烧结温度十分敏感,在1 180~1 200 ℃范围内,发泡陶瓷试样的体积膨胀了2倍。外加SiC发泡剂能显著提高抛光渣体系发泡陶瓷试样的发泡能力,使其气孔尺寸增加10倍左右,但气孔形状不规则,孔壁结构中存在微小气孔。研究结果表明,外加发泡剂后,抛光渣自身发泡形成的壁孔结构使发泡陶瓷气孔率增加,强度损失较少,导热系数降低,且壁孔结构中的气孔分布不均匀,使发泡陶瓷的热稳定性降低。     

Preparation and characterization of porous ceramics from nickel smelting slag and metakaolin

Porous ceramics with high porosity and low bulk density were prepared by using nickel slag and metakaolin as the primary raw materials, glass powder as flux, and SiC as the foaming agent. The content of nickel slag and foaming agent had a significant effect on the bulk density, porosity, and flexural strength of the porous ceramics. The porous ceramics with the best properties were obtained at 1100 °C for 30 min with 50 wt% nickel slag, 40 wt% metakaolin, 10 wt% waste glass, and 0.8 wt% SiC. It had a low bulk density (as low as 245 kg/m³), high flexural strength and compressive strength (0.6 MPa and 1.17 MPa, respectively), and high porosity (about 89.8%). The nickel slag was magnetically separated as well. The density of nickel slag powder could be reduced via magnetic separation, and there was no significant change in the crystal structure of the raw material. Compared with porous ceramics prepared using nickel slag without magnetic separation, ceramics subjected to magnetic separation had lower bulk density, higher porosity, and the same phase composition. This study can be used as an indicator for the application of nickel slag in porous ceramics, which is of great significance in providing a great substitute nickel slag towards recovery and utilization.     

以铜尾矿制备发泡陶瓷墙板的研究

以山西某地铜尾矿作为主要原料制备轻质、高强度发泡陶瓷墙板,并采用抗压强度测试仪、XRD测试仪作为主要检测手段,研究铜尾矿加入量、烧成制度以及发泡剂对发泡陶瓷墙板物理性能的影响。研究结果表明:铜尾矿加入量控制在85%左右,SiC微粉0.25%,烧成温度1170℃保温40min,可以试制出适合发泡陶瓷隔墙板性能的产品。通过规模化生产中试,产品密度437.52kg/m^3,抗压强度9.77MPa,产品外观孔径0.5-1.5mm,满足实际应用要求。     

以硼砂为助熔剂使用含钛高炉渣制备发泡陶瓷

以紫色页岩、含钛高炉渣为原料,硼砂为助熔剂,碳化硅为发泡剂制备发泡陶瓷,通过对气孔率、闭孔率、孔径分布、表观密度、抗压强度、导热系数进行测量,研究了原料配比和硼砂添加量对发泡陶瓷气孔结构和物理性能的影响。结果显示:当原料中含钛高炉渣比例增加时,试样的平均孔径增加,气孔均匀性下降;硼砂的加入会使试样抗压强度降低,孔隙率增大,导热系数变小。当发泡陶瓷原料配比(质量分数)为高炉渣30%,页岩70%,添加4%的硼砂和0.2%的碳化硅时,制备出的发泡陶瓷的表观密度为0.374 g·cm^-3,导热系数为0.121 W·m^-1·K^-1,抗压强度为2.59 MPa,满足建筑外墙保温发泡陶瓷的要求。发泡陶瓷主要晶相为斜长石,同时伴有部分透辉石、石英和少量的铁板钛矿。     

微胶囊发泡剂/热塑性聚酯弹性体注射发泡成型工艺研究

采用注射成型工艺制备了热塑性弹性体(TPEE)发泡材料。研究了发泡剂用量、发泡温度以及注射压力对TPEE发泡材料性能的影响。采用万能力学试验机和扫描电子显微镜(SEM)分别测试和观察了TPEE发泡材料的力学性能和泡孔结构,并测试了TPEE发泡材料的表观密度。试验结果表明:TPEE发泡材料的材料性能与发泡剂用量之间的关系为非线性关系;一定的发泡温度可以影响发泡材料的表观密度,进而影响材料的力学性能;注射压力在一定程度上影响发泡剂的发泡倍率,对发泡材料的性能以及外观产生一定的影响。在发泡剂用量为4.5份、注射温度185℃、合模时间200 s、注射压力40 MPa、注射速度30 g/s的条件下,能够得到综合性能比较理想的发泡材料。     

Effects of magnesium oxychloride and silicon carbide additives on the foaming property during firing for porcelain ceramics and their microstructure

Porcelain green bodies that were prepared with a porcelain tile powder as a major raw material, and magnesium oxychloride (MO) and silicon carbide (SiC) as additives were fired at 1000–1200°C. Effect of the additives on the foaming property for porcelain ceramics and its microstructure was quantitatively investigated to clarify the foaming origin of polished porcelain waste during firing. The experimental results show that a small amount of the mixture of both MO and SiC added into the porcelain green body causes the body foaming during firing more significantly, compared to the addition of either SiC or MO. The foaming of porcelain green body with only SiC is more remarkable than that of the porcelain green body with only MO at the same content and firing conditions. The MO accelerates the foaming of porcelain green body with SiC during firing. In addition, the foaming mechanism was also discussed.     

注塑成型低发泡PP的研究

采用注塑成型工艺制备了聚丙烯(PP)低发泡材料,分别探讨了发泡剂、交联剂用量及填料对PP发泡材料拉伸强度、缺口冲击强度、硬度、密度及热变形温度等性能的影响,并用扫描电子显微镜(SEM)对泡孔结构进行了观察。结果表明:当发泡剂用量为0.5phr,交联剂用量为0.05phr及CaSO4填充母料用量为10phr时,PP低发泡材料的综合性能最佳。     

软质PVC发泡材料的研究

采用化学发泡一步法模压成型制备了软质PVC发泡材料,研究了发泡剂、泡孔成核剂、改性剂等主要助剂用量对软质PVC发泡材料密度、泡孔结构以及力学性能的影响,并进行了软质PVC发泡材料的配方筛选.结果表明加入吸热发泡剂N能提高发泡体系的发泡效果,降低材料的密度,改善材料的力学性能,当发泡剂AC用量为2份,用量为0.6份时,材料的综合性能优异;当成核剂用量为1份时,体系发泡效果较好;加入粉末NBR不仅能提高发泡材料的断裂伸长率和柔韧性,还可降低发泡材料密度,改善泡孔结构;当NBR用量为20份时,发泡材料密度达到0.44 g/cm3,力学性能优异.     

The preparation of mullite foamed ceramics reinforced by in-situ SiC whiskers and their reinforcement mechanism

A SiC whisker-bonded mullite foamed ceramic was prepared by using white clay, industrial alumina and silicon powder as raw materials without solid carbon sources. The XRD, SEM, EDS, and Factsage® software were used to investigate the effect of sintering temperature on the phase composition, microstructure, compressive strength, and Young's modulus of foamed ceramics. Additionally, the synthesis reaction of in-situ SiC whiskers and the effect of their formation on the properties of ceramics were studied. The results showed that the in-situ SiC whiskers with dendrite shapes were formed after firing above 1300 °C at the expense of Si/SiO vapors as well as CO vapor, though there were no solid carbon sources in raw materials, which provided a new idea for the synthesis of SiC whiskers. The formation of SiC whiskers was helpful for improving the compressive strength and Young's modulus of mullite foamed ceramics remarkably. Furthermore, the reinforcement mechanism has been investigated systematically.