退火处理对Al3CoCrCu1/2FeMoNiTi高熵合金激光涂层组织和性能的影响

目的研究Al_3CoCrCu_(1/2)FeMoNiTi高熵合金涂层的退火时效硬化及其强化机理。方法使用激光熔覆设备,在40Cr钢上制备了Al_3CoCrCu_(1/2)FeMoNiTi高熵合金涂层,对涂层进行了退火处理。使用X射线衍射仪、扫描电子显微镜和显微硬度计对涂层进行了分析。结果涂覆态涂层为BCC单相结构,经300℃和500℃退火,涂层仍然为BCC单相;700℃退火后,涂层析出了NiTi金属间化合物相;900℃退火后,涂层由FCC相及NiTi金属间化合物组成。涂覆态和经300~700℃退火的涂层为胞粒状,经900℃退火后,涂层为板条状。经300℃退火,涂层硬度下降,但超过300℃退火,硬度比涂覆态的高。700℃退火合金硬度达到最大值924HV。退火温度升到900℃后,硬度比700℃退火的低。NiTi析出相促进了硬度提高,位错强化机制能较好解释该高熵合金的固溶强化现象。结论Al_3CoCrCu_(1/2)FeMoNiTi合金涂层具有明显的时效硬化效应,700℃退火可获得最佳的时效硬化效果。     

双组分聚氨酯涂料用改性醇酸树脂的研究

采用不同改性的短油度醇酸树脂作甲组分,异氰酸酯预聚物作乙组分,配制双组分聚氨酯涂料,探讨甲组分对双组分聚氨酯涂料性能的影响。结果表明,椰子油改性短油度醇酸树脂,颜色水白、耐黄变性能和丰满度好,可以作为高档的亮光清面漆、耐黄变的面漆用树脂;蓖麻油改性短油度醇酸树脂,颜色较深、丰满度较好、干燥速度慢及柔韧性好,可以作为普通的亮光面漆用树脂;豆油改性短油度醇酸树脂,干燥速度较快,应用于底漆和哑光面漆;合成脂肪酸改性短油度醇酸树脂,颜色水白、流平好、干燥速度慢、丰满度高及硬度高,可以作为高档的亮光面漆用树脂。     

阳离子无氟丙烯酸酯防水剂的制备及应用

以甲基丙烯酸十八烷基酯（ SMA）、甲基丙烯酰胺（ MAA）、丙烯酸羟乙酯（ HEA）和甲基丙烯酰氧乙基三甲基氯化铵（ DMC）为单体,十六烷基三甲基溴化铵（ CTAB）和聚氧乙烯醚（ AEO-20）为复合乳化剂,偶氮二异丁脒盐酸盐（ AIBA）为引发剂,采用细乳液聚合法制备无氟阳离子丙烯酸酯防水剂。分析了聚合物温度、乳化剂用量和交联剂用量（ HEA）对乳胶性能的影响。结果显示：乳化剂为 7%,HEA为 2%,反应温度为 80 ℃,反应时间为 5h,合成的乳胶性能最佳。当防水剂用量为 100 g/L时,整理后的棉织物显示了较强的疏水性能,其接触角达到 139°。经过 25次洗涤后,棉纤维仍然具有较高的接触角,说明具有优良的耐洗性能。     

竹纤维织物抗菌整理研究

以抗菌剂RUCO-BAC MED和交联剂HF按一定配比配制成整理液,采用浸轧法对竹纤维织物进行抗菌后整理,并运用晕圈法测试整理后织物的抗菌性。研究发现,经整理后的织物具有优良的抗菌效果和耐洗性能,当交联剂用量为0 g/L时,抑菌圈的半径最大。同时还就抗菌整理前后织物的物理性能进行了对比研究,结果表明:整理前后织物的断裂强力。耐摩擦色牢度变化较小。表明该整理剂适合竹纤维织物的抗菌整理。     

水性聚氨酯涂膜耐水性影响因素研究

以聚酯多元醇、甲苯二异氰酸酯为主要原料合成了水性聚氨酯乳液。研究了NCO/OH值、亲水扩链剂DMPA及交联剂TMP的用量、硬段软段质量比对乳液涂膜耐水性的影响,获得了较优的实验配比;研究了环氧树脂、蓖麻油、有机硅对水性聚氨酯的改性,实验表明,改性后的水性聚氨酯涂膜的耐水性能得到较大的提高。     

Experimental characterization of buoyancy- and surface tension-driven convection during the drying of a polymer solution

Within the framework of convection induced by evaporation, an experimental study of the drying of a polymer solution has been performed. Several visualisations of convective pattern development are presented: top view with a video camera and an IR camera, as well as visualisation in a vertical section. The appearance and origin (buoyancy- and/or surface tension-driven instabilities) of the convective structures are analysed as a function of the initial thickness and viscosity. Different regimes are obtained when comparing the lifetime of the convective patterns to the thermal transient regime induced by evaporation and to the formation of a thin viscous skin at the surface.     

氨基磺酸镍/碳化硅复合镀层组织及硬度分析

配制了氨基磺酸镍电镀液,找出了最佳镀液成分和工艺参数。使用扫描电子显微镜、超景深显微镜、库仑测厚仪、XRD衍射仪和显微硬度计对镀层进行了分析。结果表明,镀液组成最佳为氨基磺酸镍360g/L、氯化镍20g/L、硼酸38g/L;镀液温度范围在45~60℃,电流密度为5~18A/dm^3。复合镀镍/碳化硅的最大电流密度为15A/dm^3。电流密度15A/dm^2的镀速为113μm/h,镀层硬度为638HV。     

PLA/PEO共混物的结晶行为研究

共沉积技术制备了聚乳酸(PLA)/聚氧化乙烯(PEO)共混物,通过DMA和相差显微镜考察了共混物的相行为。用DSC研究了PLA/PEO共混物的结晶形貌及其动力学,由于部分相容的熔融态PEO提高了PLA分子链的运动能力,导致显著促进了PLA的结晶速率;结合偏光显微镜(POM)观察分析,结晶速率的提高源于结晶生长速率的促进,而且在低的结晶温度时的结晶速率的增加更为明显。     

Phase behavior for the poly[2-(2-ethoxyethoxy)ethyl acrylate] and 2-(2-ethoxyethoxy)ethyl acrylate in supercritical solvents

Pressure-composition (p, x) isotherms were obtained for the carbon dioxide + 2-(2-ethoxyethoxy)ethyl acrylate [2-(2-EE)EA] system at five temperatures (313.2 K, 333.2 K, 353.2 K, 373.2 K, and 393.2 K) and pressure up to 22.86 MPa. The carbon dioxide + 2-(2-EE)EA system exhibits type-I phase behavior with a continuous mixture critical curve. The experimental results for carbon dioxide + 2-(2-EE)EA mixtures are correlated using the Peng–Robinson equation of state (PR-EOS) using mixing rule including two adjustable parameters. The critical property of 2-(2-EE)EA is estimated with the Joback–Lyderson method.Experimental data up to 485 K and 206.6 MPa are reported for binary and ternary mixtures of poly(2-(2-ethoxyethoxy)ethyl acrylate) [P(2-(2-EE)EA)] + carbon dioxide + 2-(2-EE)EA, P(2-(2-EE)EA) + carbon dioxide + dimethyl ether (DME), P(2-(2-EE)EA) + carbon dioxide + propylene and P(2-(2-EE)EA) + carbon dioxide + 1-butene systems. High-pressure cloud-point data are also reported for P(2-(2-EE)EA) in supercritical carbon dioxide, propane, propylene, butane, 1-butene, and DME at temperature to 474 K and a pressure range of (8.45–206.6) MPa. Cloud-point behavior for the P(2-(2-EE)EA) + carbon dioxide + 2-(2-EE)EA system were measured in changes of the pressure–temperature (p, T) slope and with 2-(2-EE)EA mass fraction of 0.0 wt%, 5.9 wt%, 14.9 wt%, 30.3 wt% and 60.2 wt%. With 0.650 2-(2-EE)EA to the P(2-(2-EE)EA) + carbon dioxide solution, the cloud point curves take on the appearance of a typical lower critical solution temperature boundary. The P(2-(2-EE)EA) + carbon dioxide + (0.0–46.6) wt% DME systems change the (p, T) curve from upper critical solution temperature region to lower critical solution temperature region as the DME mass fraction increases. Also, the impact by propylene and 1-butene mass fraction for the P(2-(2-EE)EA) + carbon dioxide + propylene and 1-butene system is measured at temperatures to 454 K and a pressure range of (75.7 to 119.6) MPa.