金属材料拉伸试验结果测量不确定度评定研究

为评定金属材料拉伸试验的结果测量不确定度 ,以轧制厚度为 18mm的Q2 3 5B板材矩形带头短比例试样为例 ,建立了不确定度计算的数学模型 ,确定了影响试验结果 (ReL、Rm)的下屈服力FSL、最大力Fm、试样原始厚度a及试样原始宽度b等各项因素 ,计算出了各种因素的标准不确定度 ,得出拉伸试验结果 (ReL、Rm)的扩展不确定度 ,并给出最终测量结果的表达式 :下屈服强度ReL、抗拉强度Rm的最终测量结果分别为 (3 0 5± 5 )MPa和 (4 3 5± 10 )MPa。     

影响冷轧无取向电工钢磁性能检验结果的因素

随着我国电机行业快速发展,冷轧无取向电工钢的需求量逐年增加,针对这一现状对冷轧无取向电工钢磁性能检验结果进行分析,其中包括制样设备、环境温度、试样尺寸、试样重量、试样密度、检验设备等。分析结果表明:冷轧无取向电工钢随着剪切次数、质量、密度增加,铁损都增大,磁感都降低;随着环境温度升高,铁损和磁感降低。分析影响冷轧无取向电工钢磁性能检验结果的因素,对提高检验结果的精确度具有重要意义。     

金属薄板塑性应变比(r值)测量不确定度的评定

为评定深冲钢塑性应变比(r值)的测量不确定度,以厚度规格为80mm的St14试样为例,建立了计算r值不确定度的数学模型,确定了影响r值的各项因素,主要有试样原始宽度及其变形、试样原始标距及其变形4个输入量引入的不确定度和数值修约带入的不确定度,计算出了各因素的标准不确定度,r值的扩展不确定度为0.08,St14试样r值最终测量结果表达式为r=1.84±0.08。     

夏比摆锤冲击试验的质量保证

阐述了用质量控制方法分析影响钢管夏比冲击试验的主要因素,用质量评定方法维持和提高试验的水平。在检测工作中,应充分认识材质、测量设备、试样制备、试验温度控制及人员等对试验结果的影响,及时发现问题,采取相应的纠正措施,确保试验结果的准确性和可靠性。     

拉伸试样加工方法对厚规格延伸性能的影响

通过对拉伸试样采用全厚度和减薄方法的对比分析,试样在同等条件下忽略外在影响因素,各项性能应在规定的误差范围内。因受生产加工和检验加工等因素影响,不同的试样加工方法对钢板延伸性能有一些影响,其影响程度与铸坯的内部质量和中心偏析有关。实际生产中由于铸坯中心偏析的不可避免性等因素影响,采用全厚度拉伸试样更能反映材料的实际特性,延伸性能更为稳定。建议在试验设备能力允许条件下采用全厚度拉伸试样。     

用于测量电工钢片直流磁性的装置

本实用新型涉及测量电工钢片直流磁性的装置。其解决现有技术中存在的对磁场强度试样厚度有限定、或体积大、试样磁化不均匀、结构复杂、或试样加工复杂，并且每次实验均要进行绕线、不能重复使用、加大了测量时的偶然误差等不足。解决的技术措施：用于测量电工钢片直流磁性的装置，包括底板、安装在底板上的空心线圈、初级线柱、次级线柱、设在空心线圈两端的挡板，其在于有两个空心线圈并列排放，在挡板的外侧设有衔接片，衔接片连接在与底板固定的垫板上。     

非晶薄带动态磁性的开路测量

本文叙述开路测量非晶薄带动态磁性的一种方法。该法基于正弦低磁感条件下测量磁感和磁场的峰值以及它们之间的相角。由于薄带厚度一般不超过20μm,可以显著减小退磁场的影响而不需要进行修正,故此方法很适合于测量非晶薄带的高频磁性。通过细致校正测量线圈及补偿零相角来保证测量精度。     

烧结机机尾断面红层过厚的原因分析及对策

针对安钢烧结厂90/105m2烧结机机尾断面红层相对较厚的情况,从原料条件、工艺状况、设备因素等方面查找原因,提出了具体对策,通过控制适宜的燃料粒度,降低燃烧带厚度;提高料温,减少过湿层的影响;强化制粒,改善料层透气性;减少系统漏风等措施,增加通过料层的有效风量,降低机尾红层厚度,提高烧结矿产质量.     

影响电工钢磁性能检测准确性因素研究

本文探讨了TD8100磁性能测试仪应用过程中影响分析结果准确性的因素,从仪器结构入手,主要研究了仪器开机预热时间、试样质量、试样比重、试样在方圈内放置位置、保存方式、保存时间对电工钢磁性能分析结果的影响。     

测量非金属夹杂物数量的方法和浇注试样所用的铸型

正美国专利US8155430本发明涉及一种测量铸造金属样品中非金属夹杂物数量的方法。本发明的方法包括:制备铝合金铸造试样;用CCD摄像设备或其它摄像方法捕捉试样断口的矩形断面表面图像;对捕捉到的图像进行加工,显示色密度;采用预定的临界值对加工过的图像进行数字化处理,计算一个或多个预定面积上的像素集群。本发明方法的特点还包括在捕捉试样断面图像之     

高温合金母合金真空冶炼中炉前快速分析的取制样方法探讨

高温合金母合金的成分范围控制较窄,应用综合检测手段,建立了高温合金母合金中主量、微量及痕量元素的炉前快速分析方法。使用30 mm的铝刚玉材质取样杯,在真空感应炉中采用二次浸没法取高温合金母合金熔液,凝固后快速冷却完成取样。在样品的尾部切割厚约8 mm的第1试样,用于辉光放电质谱仪(GDMS)测试其痕量元素含量;在剩下的样品上再切割厚约5 mm第2试样片,并切割成宽约5 mm、长30 mm的长条,经打磨后剪成质量为0.5~1.0 g的颗粒,丙酮清洗后用于碳、硫和氧、氮、氢测试;在剩余部分样品上继续切割厚约8 mm的第3试样,采用X射线荧光光谱仪(XRF)测试主量元素含量,然后使用火花放电原子发射光谱仪测试硼元素含量;最后利用实验室数据对接系统汇总检测数据,将检测结果快速传输给冶炼控制室。实验研究了取样杯内直径尺寸、热处理温度和浸没次数对炉前样内部质量的影响,同时考察了取样杯材质对炉前样品中杂质元素的影响以及不同元素在炉前样柱体分布情况,通过制样方法和仪器设备选择优化测试时间,实现了在25 min内完成40余种主量、微量以及痕量元素的炉前快速分析。方法在高温合金母合金冶炼中得到了应用,为有效控制其主量元素以及高温合金纯净化提供准确数据。     

Sample suitability for the detection of minor white cell populations (microchimerism) by polymerase chain reaction

BACKGROUND: There is increasing use of highly sensitive testing with polymerase chain reaction (PCR) to study white cell microchimerism after transfusion and transplantation. This study investigated possible artifactual sources of allogeneic sample contamination before PCR testing. STUDY DESIGN AND METHODS: Quantitative Y-chromosome PCR was used to study microchimerism among transfused patients with sickle cell disease (SCD) and thalassemia by using residual specimens from the clinical laboratory. High levels of circulating male white cells among transfused patients with SCD but not thalassemia led to concern over the artifactual origin of male cells. To investigate, paired specimens were collected from 26 female SCD patients: one specimen underwent processing only for PCR, while the other underwent testing in the clinical laboratory before PCR as a process control. All laboratory instruments were also assessed for their ability to impart male allogeneic cells to aliquots of female blood. RESULTS: Thirty-three (31%) of 107 SCD samples, but 0 of 20 thalassemia samples, gave a high-level PCR signal. One of 26 paired samples that was not exposed to clinical laboratory equipment had low-level PCR positivity while 10 of the 26 became strongly positive after testing on a blood cell analyzer and a reticulocyte analyzer. Sixteen of 32 female samples became positive after reticulocyte analysis, while none became positive after blood cell analysis. Samples from thalassemia patients tested PCR-negative because reticulocyte counts had not been performed. CONCLUSION: Allogeneic cell contamination is common with clinical laboratory equipment. These samples may not be suitable for microchimerism studies. In addition to method controls, process controls should be employed where appropriate.     

扫描电镜能谱仪测定不锈钢中镍含量测量结果的不确定度评定

为了解扫描电镜能谱仪定量分析结果的准确度,采用扫描电镜能谱仪对SUS-101g不锈钢中镍含量进行定量分析,对影响定量分析结果的不确定度分量包括重复性测定、修正方法、标准物质、实验室环境及设备校准证书等进行逐一讨论,并对各影响因素的不确定度分量进行计算和合成,计算扩展不确定度。测量过程执行标准GB/T 17359—2012《微束分析 能谱法定量分析》。测量不确定度的评定结果表明:影响不确定度的来源主要有重复性测定、修正方法和设备校准证书3个方面,而标准物质和实验室环境的影响根据实际情况可以忽略。不确定度报告可表示为:测定结果镍质量分数为9.92%,扩展不确定度U=0.74%,取包含因子k=1.96。     

EDP registration of the types of tests, working procedures and diagnosis in a department of histopathology. Minimum dataset for assessment of the workload

The aim of the study was to develop a computer-based system for measuring workload in a department of histo- and cytopathology using routine registration of a minimum dataset. A group with representatives from the laboratory technicians, the pathologists and the secretaries defined 18 types of specimens. By studying each step of specimen processing it was shown, that 14 items for technical details could cover all the work done in the department. This information was collected in a computer-based system connected to the hospital network. The measurement of workload is essential for the efficient management of laboratory services. The registration of specimen types and a minimum dataset for specimen processing describes the work done in a department of histo- and cytopathology.     

温轧工艺对Fe-6.5％Si薄板织构的影响

高硅钢具有优异的软磁性能,是中高频电机铁心的理想材料。采用双辊连铸-热轧-温轧-退火工艺,制备了厚度为 0.30 mm的6.5 %Si薄板。利用X射线衍射仪和磁性测量,研究了不同温轧工艺对6.5 %Si薄板轧制及退火织构、最终磁性能的影响。结果表明,温轧温度越低,越有利于温轧板心部形成{001}〈0vw〉织构,600 ℃和500 ℃轧制的试样经退火后主要是γ织构,而400 ℃轧制的试样退火后则同时含有γ织构及强度较高的η织构,其对应的磁感值高;同样的温轧温度,二次轧制的温轧板中并未形成{001}〈0vw〉织构,且试样经退火后也没有形成η织构,其磁感比一次轧制的试样低。因此,低温一次轧制,有利于试样在退火过程中形成有利的η织构而提高磁感。     

Influence of a solution treatment on the evolution of through‐thickness texture gradients in dry cold rolled and recrystallized low carbon steel

The influence of a solution treatment on the evolution of through‐thickness texture gradients in a low carbon steel was studied. In order to intensify through‐thickness variations of the strain state, the samples were cold rolled dry, i.e. without lubrication. The evolution of the texture and the microstructure during rolling and recrystallization was tracked by X‐ray texture analysis and TEM microstructure investigations. The strain distribution during rolling was simulated for several layers of the rolled sheets by the finite element method. After the rolling deformation, a specimen taken directly from the hot band showed pronounced through‐thickness texture gradients, whereas the solution treated specimen showed a rather uniform rolling texture in all layers analyzed. Analysis of the friction behaviour between the different specimens and the roll material points to a much higher friction between the softer hot band and the rolls. This leads to stronger through‐thickness variations in the strain state and, thus, to the pronounced texture gradients observed. The texture gradients in the recrystallized samples reflected those of the as‐rolled sheets. In the center layer of the hot band specimen and in all layers of the solution treated specimen characteristic though notably weakened typical plane strain recrystallization textures formed; the textures in outer layers of the hot band sample were even almost random. These weak recrystallization textures could be attributed to the highly inhomogeneous as‐deformed microstructure.     

脉冲磁场强度对钛处理低碳钢凝固过程的影响

采用自发研制的脉冲磁场发生装置将脉冲磁场非接触式地施加到钛处理低碳钢的凝固过程中,利用金相显微镜、扫描电镜和能谱仪研究了不同强度的脉冲磁场对试样的宏观形貌、枝晶和组织的影响。结果表明,随着脉冲磁场强度的增加,试样的宏观表面逐渐变得平整;枝晶和组织随着脉冲磁场强度的增加逐渐细化,但达到一定强度后,继续增加又出现了相反的结论。由此可以推断,脉冲磁场强度对枝晶和组织的影响存在一个最佳值。     

控制图在铜精矿中银含量检测质控管理中的应用

目前,测量不确定度的评估技术大致可以分为两类:“bottom-up”和“top-down”。“bottom-up”技术过程繁复且对化学检测实验室测量不确定度有局限性,而“top-down”技术中的控制图法不仅操作简便,还可以弥补“bottom-up”技术评定不确定度出现的局限性,控制图法作为实验室质控管理的重要手段已被广泛认可。依据标准GB/T 27407—2010,探讨了控制图在铜精矿中银含量检测质控管理的应用,对实验室日常分析工作中铜精矿质控标准样品(GBW 07166)中银含量系列结果的正态性、独立性与分辨力进行检验,作控制图,t检验并评定方法的不确定度及分析其合理性。铜精矿中银含量质控样品实测数据控制图的计算结果如下:平均值为43.8g/t,期间精密度为1.6g/t,扩展不确定度为3.2g/t,接受系列测量结果的正态性、独立性与分辨力适应性的假定,控制图中没有失控点,整个实验室检测系统处于受控状态。控制图法可反映实验室较长一段时间内的检测水平,适用于检测实验室的质量控制,具有实际应用价值。     

Faulty washers and soiled micropipettors may generate false positive serological results

BACKGROUND: Serological markers such as HBsAg and anti-HIV may be present in serum at very high concentrations and this may give rise to erroneous diagnoses due to cross-contamination. OBJECTIVES: To investigate poor equipment maintenance and use, including contamination with human serum, as a potential source of erroneous assay results. STUDY DESIGN: The potential of microtitre plate washers and micropipettors to transfer material between microplate wells and between specimens was examined. For the study of micropipettors we recruited 19 UK diagnostic laboratories. RESULTS: Four out of seven plate washers in use, until adjusted, had the potential to cause false positive HBsAg reactions. The centering of the probes that delivered the wash fluid, delivery pressure, wash volume and the use of a pre-programmed card to direct the washing procedure were important variables. We investigated soiling of tip cones of micropipettors. In every laboratory human IgG could be detected in at least a third of eluates from micropipettor tip cones; only 31 (14%) of 222 showed no evidence of contamination with human serum. Only one laboratory submitted eluates devoid of specific antibodies. Anti-HAV was the marker most commonly found (n = 68), followed by HBsAg (n = 27) and anti-HIV (n = 20). Seven micropipettor eluates from two laboratories were radioactively contaminated. CONCLUSIONS: Recommended precautions are regular checking, cleaning and servicing of equipment, care in interpreting weak reactions, reference back to serum left on the clot of the original specimen and testing of a follow up specimen. Poorly maintained immunoassay equipment can readily generate false positive results due to low-level cross-contamination, particularly with the current highly sensitive HBsAg and anti-HIV assays.     

便携式X射线荧光光谱仪检测贫铀棒材表面镍锌镀层厚度

为了确保贫铀棒材表面防腐性能满足使用要求,需要准确地测量产品表面的镍镀层和锌镀层厚度。采用便携式X射线荧光光谱仪(PXRF)对贫铀棒材表面双镀层的各层厚度进行检测,实现了对镍镀层和锌镀层厚度非破坏性的测量。选用特征谱线强度分布均匀的镀层样品和未镀镀层的贫铀基体样品,采用PXRF检测,结果表明,基体射线对检测谱线无干扰。分别选取相同厚度镍镀层、不同厚度锌镀层的样品,相同厚度锌镀层、不同厚度镍镀层的样品,以及镍镀层、锌镀层厚度均不相同的样品,采用PXRF进行检测,结果表明,实验方法可识别相同基体上不同厚度的镍镀层和锌镀层,可实现镍锌组合镀层中两种镀层厚度的同时测量。根据贫铀棒材样品结构特点和镍镀层和锌镀层厚度的技术要求,设计制作了对比试样,分别绘制贫铀棒材样品镍镀层和锌镀层厚度与其对应特征峰强度的校准曲线,结果表明,校准曲线线性相关系数r均不小于0.999 4。采用实验方法检测贫铀棒材样品表面镍镀层和锌镀层厚度,同时在任意圆周上均匀地取6个检测点,采用金相显微镜法进行检测求得平均值,结果表明,实验方法测定结果相对标准偏差(n=6)不大于5.1%;与金相显微镜法基本一致,两种方法差值为-1.57~1.70 μm。