Test Pins Research Articles

Analysis of fuel pin behavior under slow-ramp type transient overpower condition by using the fuel performance evaluation code ‘FEMAXI-FBR’

FEMAXI-FBR has been developed as the one module of the core disruptive accident analysis code ‘ASTERIA-FBR’ in order to evaluate the mixed oxide (MOX) fuel performance under steady, transient and accident conditions of fast reactors consistently. On the basis of light water reactor (LWR) fuel performance evaluation code ‘FEMAXI-6’, FEMAXI-FBR develops specific models for the fast reactor fuel performance, such as restructuring, material migration during steady state and transient, melting cavity formation and pressure during accident, so that it can evaluate the fuel failure during accident. The analysis of test pin with slow transient over power test of CABRI-2 program was conducted from steady to transient. The test pin was pre-irradiated and tested under transient overpower with several % P 0/s (P 0: steady state power) of the power rate. Analysis results of the gas release ratio, pin failure time, and fuel melt radius were compared to measured values. The analysis results of the steady and transient performances were also compared with the measured values. The compared performances are gas release ratio, fuel restructuring for steady state and linear power and melt radius at failure during transient. This analysis result reproduces the measured value. It was concluded that FEMAXI-FBR is effective to evaluate fast reactor fuel performances from steady state to accident conditions.

A DFT Strategy for an Industrial Communications SoC with JTAG

In this paper a system level DFT strategy with JTAG is presented to test an industrial communication and control SoC . A SoC generally integrates that microprocessor, memories, some function blocks, PLL, D/A, A/D, etc. Cores originating from different sources need different test strategies. The different test techniques are used in testing of core-based SoC system which combines scan chains, Memory-BIST and Boundary-Scan. A SoC test with JTAG architecture is implemented through a real life case (0.18µm, million gates chip). The test pin counts are reduced, test time for board test is shorter and high test coverage is achieved.

Test-Architecture Optimization and Test Scheduling for TSV-Based 3-D Stacked ICs

Through-silicon via (TSV)-based 3-D stacked ICs (SICs) are becoming increasingly important in the semiconductor industry. In this paper, we address test architecture optimization for 3-D stacked ICs implemented using TSVs. We consider two cases, namely 3-D SICs with die-level test architectures that are either fixed or still need to be designed. We next present mathematical programming techniques to derive optimal solutions for the architecture optimization problem for both cases. Experimental results for three handcrafted 3-D SICs comprising of various systems-on-a-chip (SoCs) from the ITC'02 SoC test benchmarks show that compared to the baseline method of sequentially testing all dies, the proposed solutions can achieve significant reduction in test length. This is achieved through optimal test schedules enabled by the test architecture. We also show that increasing the number of test pins typically provides a greater reduction in test length compared to an increase in the number of test TSVs. Furthermore, we show that shorter test lengths are generally achieved with the larger, more complex dies lower in the stack. This is because test data must pass through every die lower in a stack in order to reach its target die, and with the larger dies lower in the stack, more test bandwidth may be provided to these dies using fewer routing resources.

Mechanical and tribological studies of polymer hybrid nanocomposites with nano reinforcements

Developments of nanoparticle reinforced plastics are of growing interest towards the emergence of new materials which enhance optimal utilization of natural resources and particularly of renewable resources. The effects of nanoparticles as fillers in glass-epoxy composite systems on the mechanical and tribological properties have been discussed in this article. The mechanical properties such as tensile strength, impact strength, flexural strength, and hardness have been studied in accordance with ASTM standards. The composites employed in the study have been fabricated using hand lay-up technique. By varying notch radius impact strength is studied. The clay and silica used in the present system were treated with 3-aminopropyltriethoxysilane. The effect of variants in sliding speed, time and applied load on the wear behavior of polymer nanocomposites is studied by measuring the weight changes and observing the surface features using scanning electron microscope. In the experiments with wear test pin having flat face in contact with hardening rotating steel disc, sliding speed, time and loads in the range of 640–1000 RPM, 300–900 s and 5–25 N respectively was used. It is observed that wear rate increases with increasing applied load, time and sliding speeds.

Antimicrobial Efficacy of Surface-Coated External Fixation Pins

In clinical applications, colonization of metal implants by adhesive and biofilm-forming bacteria not only prolong healing but create additional healthcare costs for implant revision and antimicrobial treatment. An in vitro assay was established investigating the antimicrobial surface activity of external fixation pins intended for use in bone fractures and deformities. Test articles made out of stainless steel and coated with a polymer-containing nanoparticulate silver were compared to non-coated reference controls out of stainless steel, copper and titanium. Staphylococcus epidermidis, known as a predominant cause for implant-related infections was used as test organism. Test pins and bacteria were incubated for a period of 20 h found to be sufficient for initiating biofilm formation. After removing non- and low-adherent bacteria by rinsing, two methods were used to isolate high-adherent (sessile) bacteria from the implant surfaces. Besides shaking the implants in a solution containing small glass beads, a cytobrush technique was used to mechanically harvest viable bacteria. Finally, the amount of detached bacteria was determined by plate counts. Several parameters identified to be critical within the different removal procedures such as the inoculum concentration and the shaking time in the presence of glass beads as well as time of the cytobrush treatment were analysed. The final test scheme resulted in the use of an inoculum of 10(5) colony forming units (CFU) per millilitre, ten rinsing steps for the removal of low adherent bacteria and 5 min of shaking in the presence of glass beads, detaching the high-adherent bacteria. Due to subjective variations impacting the outcome of the procedure, the cytobrush technique was not favoured and finally rejected. Using the in vitro assay developed, it could be demonstrated that fixation pins coated with silver show a 3 log step reduction in the number of biofilm-forming bacteria compared to a non-coated stainless steel or titanium implant. Pins made out of copper showed the highest antimicrobial efficacy, as the number of detached bacteria was found to be below the detection limit, they served as a positive control within this test.

S043032 ねじりピンテスト法による溶射被膜の付着強度評価に関する研究([S04303]環境調和型の表面改質および薄膜コーティング(3))

To establish the adhesive strength evaluation method of thermal sprayed coating with high adhesive strength, the torsion pin test method is newly proposed. In this study, fracture strength of WC-12Co thermal sprayed coating is investigated under combined torsion and tension experimentally and analytically. Stress distributions at around interface edge are analyzed by FEM analysis and are approximated by the expression o=KR^-λ where K means the strength of the stress field. K is found to be independent on a clearance △r between pin and hole. FEM analysis shows that the critical stress distributions at the interface edge are resemble each other for the different pin diameter.

Delamination Strength Evaluation of Thermal Sprayed Coating by Torsion Pin-Test Method

To establish the shearing delamination strength evaluation method of thin coating layer with high strength, thermal sprayed coatings were tested by newly proposed torsion pin test method with tension. In this study, delamination strength of WC-12Co thermal sprayed coating is investigated experimentally and analytically. Stress distributions at crack tip singular point on delaminated surfaces are analyzed by FEM and is approximated by the expression σ=Kr-λ where K means a size of the field of singular stress. The critical combinations of shear stress intensity factor (Ks) with tensile stress intensity factor (Ka) which means delamination criteria of coating under combined shear and tensile loadings can be obtained for various pin clearance. These combinations were found to be independent of pin clearance.

Adhesive Strength Evaluation of Erosion-resistant Sprayed Coatings by Tensil Pin Test

Adhesive Strength Evaluation of Erosion-resistant Sprayed Coatings by Tensil Pin Test

SOC Test Architecture and Method for 3-D ICs

3-D integration provides another way to put more devices in a smaller footprint. However, it also introduces new challenges in testing. Flexible test architecture named test access control system for 3-D integrated circuits (TACS-3D) is proposed for 3-D integrated circuits (IC) testing. Integration of heterogeneous design-for-testability methods for logic, memory, and through-silicon via (TSV) testing further reduces the usage of test pins and TSVs. To highly reuse pre-bond test circuits in post-bond test, an innovative linking mechanism shares TSVs and test pins of the 3-D IC. No matter how many layers are there in the 3-D IC, a large portion of TSVs and test pins is reserved for data application. Therefore, smaller post-bond test time is expected. A test chip composed of a network security processor platform is taken as an example. Less than 0.4% test overhead increases in area and time between 2-D and 3-D cases. Compared with the instinctively direct access, TACS-3D reveals up to 54% test time improvement under the same TSV usage.

Sol–gel development activities at IGCAR, Kalpakkam

Sol–gel based fuel fabrication processes have the potential to be the nuclear fuel fabrication processes in the future. Hence development of sol–gel technology for nuclear fuel fabrication is being the pursued in the Department of Atomic Energy in India. As a part of the efforts, a laboratory scale facility for fabrication of test fuel pins for irradiation in the Fast Breeder Reactor (FBTR), Kalpakkam has been set up at the Indira Gandhi Centre for Atomic Research, Kalpakkam, India. These fuel pins will be vibropacked with sol–gel derived microspheres or stacked with pellets obtained by compaction of sol–gel derived microspheres. The facility is aimed at demonstration of the remote operation of the fuel pin fabrication process through the sol–gel route. A capsule containing three test pins from this facility will be irradiated in FBTR. The design features of the facility and the test fuel pins are described in this paper.

Characterization of Splitting Behavior of Bamboo Culms

Bamboo is viewed as a sustainable and highly renewable material that may be grown in any temperate climate zone. Interest in the engineering properties of bamboo and the use of bamboo in engineered construction is growing. Although often having superior mechanical properties than readily available sawn timber, bamboo, being largely an unidirectional fibrous material, is very susceptible to longitudinal splitting. Despite being the dominant limit state in many applications, very little previous work has addressed the characterization of bamboo splitting failure. The present research focuses on the development of a split pin test method for characterizing the splitting strength of bamboo culms. The proposed split pin test uses a full culm section test, thereby eliminating some of the complexities of partial culm tests. Results of a pilot study of the split pin test having similar specimens with different split pin diameters yielded consistent results and variations less than that of the previously standardi...

IEEE 1149.1의 실시간 신호 시험 구조 설계

보드에 장착된 소자들을 테스트하기위해 제안된 IEEE 1149.1 시험 구조는 입력으로 TDI 핀을 사용하고 출력으로 TDO 핀을 사용하는 커다란 직렬 쉬프트 레지스터이다. IEEE 1149.1은 보드 수준에서의 테스트는 완벽하게 수행하지만 보드가 시스템에 장착되고 난 후의 수행 중인 시스템 수준에서의 실시간 동작클럭 속도로의 테스트에는 문제가 있다. 즉시험대상 핀의 실시간 동작신호를 시험하기 위하여 직렬 시프트 레지스트 체인들의 출력속도를 동작 클럭의 쉬프트레지스터 배수 이상의 속도로 작동 하여야 한다. 본 논문에서는 시스템 클럭과 동일한 속도로 실시간 신호를 캡쳐하기 위한 실시간 신호 시험 구조를 설계하고 시험 절차를 제안하였다. 제안한 실시간 신호 시험 구조를 Altera의 Max+Plus 10.0을 사용하여 제안한 시험 절차에 따라 시뮬레이션을 수행하였으며, 이를 통해 제안한 시험구조가 정확히 동작함을 확인하였다. IEEE 1149.1 test architecture was proposed to support the test of elements within the boards. It is a large serial shift register that uses the TDI pin as an input and the TDO pin as an output. Even though it performs the board level test perfectly, there is a problems of running system level test when the boards are equipped to the system. To test real time operation signal on test pin, output speed of serial shift register chain must be above double clock speed of shift register. In this paper, we designed a runtime test architecture and a runtime test procedure under running system environments to capture runtime signal at system clock rate. The suggested runtime test architecture are simulated by Altera Max+Plus 10.0. through the runtime test procedure. The simulation results show that operations of the suggested runtime test architecture are very accurate.

310 ねじりピンテスト法による溶射皮膜の付着強度評価に関する研究(OS3-3 薄膜・コーティング材の機械的特性と界面強度特性)

To establish the adhesive strength evaluation method of thermal sprayed coating xth high adhesive strength, torsion pin-test is newly proposed pin test method. In this study, shearing adhesive strength of WC-l2Co thermal sprayed coating is investigated experimentally and analytically. In torsion pin-test experiment, the result is not scattered. Stress distribution at stress singular point on fractured surfaces are analyzed by Finite-Element-Method and is approximated by the expression o=KR From the approximated curve, it is found that the coefficient K of stress singularity and stress singularity index 2 are nearly becoming constant.

Tribological and nanoscale research on model friction couples intended for hip joint prostheses

The paper presents the results of tribological and nanoscale research on model friction couples intended for hip joint prostheses. The tribological tests were performed by means of reciprocating pin on plate testing machine. The investigated friction pairs contained plates rubbing against polymer pins. The test plates were made from seven kinds of ceramics containing different concentrations of ZrO2 and Al2O3, and two kinds of Co–Cr alloy. The test pins were made from UHMWPE. Tribological tests were performed in conditions of Ringer solution circulation. On the basis of friction force measurements, for each investigated friction couple, the average coefficient of friction was calculated. On the basis of total wear measurements, for each investigated couple, the wear intensity was calculated. Before and after every test, the plates and pins were analysed by means of atomic force microscopy. The difference in plate surface roughness was determined by the results of the atomic force microscopy analyses.It was stated, that in the case of investigated friction joints, working under reciprocating motion, the wear and friction coefficient correlates with the surface roughness of plate specimens. For the plates with higher surface roughness, the lower friction coefficient and also lower UHMWPE pin wear intensity were observed. The friction coefficient and wear intensity were increasing with decreasing surface roughness. The correlation is confirmed by the differences in material transfer process. Considering investigated friction couples, the pin polymer material is smeared on the ceramic plates with the highest surface roughness creating a thin polymer film. In the case of ceramic surfaces with the lowest surface roughness, the strong adhesive bounds are created and some large particles of polymer are transferred to ceramic surface.

Particle size effect on abrasion resistance of mottled cast iron with different retained austenite contents

Effects of particle abrasive sizes on wear resistance of mottled cast iron with different retained austenite contents were studied. Abrasive wear tests using a pin test on alumina paper were carried out, using abrasive sizes between 16 μm and 192 μm. Retained austenite content of the matrix was determined by X-ray diffraction. The wear surface of samples and the alumina paper were examined by scanning electron microscopy for identifying the wear micromechanism. The results show that at lower abrasive sizes the mass loss was similar for the iron with different austenite contents. However, at higher abrasive sizes the samples with higher retained austenite content presented higher abrasion resistance. For lower abrasive sizes tested, samples with higher and lower retained austenite content both presented microcutting. On the other hand, the main wear micromechanism for the samples with higher retained austenite content and higher abrasive sizes was microploughing. The samples with lower retained austenite content presented microcutting and wedge formation at higher abrasive sizes. Higher abrasive size induced more microcutting in samples with lower retained austenite. The iron with lower retained austenite content presented wider grooves for the different abrasive sizes measured. SEM on the abrasive paper used on samples with higher retained austenite showed continuous and discontinuous microchips and the samples with lower retained austenite showed discontinuous microchips at 66 and 141 μm. This research demonstrates the relation between abrasive size, wear resistance, groove width and wear micromechanism for mottled cast iron with different retained austenite contents.

Tempering temperature effects on abrasive wear of mottled cast iron

The effects of different tempering temperatures (300–600 °C) on abrasive wear resistance of mottled cast iron were studied. Abrasive wear tests were carried out using the rubber-wheel test on quartz sand and the pin test on Al 2O 3 abrasive cloths. The retained austenite content of the matrix was determined by X-ray diffraction. The wear surface of the specimens was examined by scanning electron microscopy for identifying the wear micromechanism. Bulk hardness and matrix hardness before and after the tests were measured. The results showed that in the two-body (pin-on-disc test) system, the main wear mechanism was microcutting and high matrix hardening was presented. The wear rates presented higher correlation with the retained austenite than with the bulk and matrix hardness. In the three-body system (sand–rubber wheel), the wear surfaces presented indentations due to abrasive rolling. The wear rates had better correlation with both the bulk and matrix hardness (before and after the wear test) than with the retained austenite content. There are two groups of results, high and low wear rates corresponding to each tribosystem, two-body abrasive wear and three-body abrasive wear, respectively.

Scalable and bijective cells for C-testable iterative logic array architectures

In this study, a novel idea is proposed to test arithmetic circuits with both acceptable number of test patterns (NTP) and hardware overhead (HO). First, highly scalable full adder and full substractor are proposed. A scalable cell consists of n bit-level cells and has both hardware and bijective scalability. These simple scalable cells establish the relationship between the NTP and the HO, which is a function of n. By adjusting the value of n, we can obtain an optimal balance between HO and NTP. An iterative logic array (ILA) based on these scalable cells will still be C-testable. Based on the novel bijective and scalable cells, the authors propose C-testable designs for multiplier-accumulator (MAC), N-tap finite impulse response (FIR) filter and matrix multiplication, where the (HO, NTP) pairs with n=2 are only about (4.87%, 74). For 4×4 matrix multiplication, the total test time of the proposed method is only about 0.19% of that with the scan-chain method. With scalable and bijective cells, all the proposed ILA solutions can be connected together into a bigger non-homogeneous ILA and save lots of test pins and build-in self-test (BIST) area. In addition, the proposed scalable cells induce a simple and systematic way to have balanced results. The proposed technique makes the ILA-based DFT schemes more practical, systematic and useful for real-world complex applications.

Design-for-testability techniques for CORDIC design

In this paper, we propose two C-testable design-for-testability (DFT) architectures for coordinate rotation digital computer (CORDIC) design. The first design is achieved by using scalable cells. A scalable cell consists of n bit-level cells and has both hardware and bijective scalability. These simple scalable cells establish the relationship between hardware overhead (HO) and number of test patterns (NTP). Both HO and NTP change as n varies. By adjusting the value of n, we can obtain an optimal balance between HO and NTP. Based on these scalable cells, the iterative logic array (ILA) will be still C-testable. For the first proposed design, the HO and NTP for n=2 are 5.37% and 74, respectively. The second one is achieved by the reorganized test sequences, where the HO and NTP are only 3.15% and 18, respectively. The first design can be connected into a non-homogenous ILA for saving lot of test pins and built-in self-test (BIST) area; in the second one, the special properties of the sequences reduce HO/NTP significantly.

Wear of spheroidal graphite cast irons for tractor drive train components

This study was prompted by a desire to improve the wear resistance of power transmission components in rear axle drives on commercial farm tractors. Reciprocating wear tests were conducted under lubricated and non-lubricated conditions on three spheroidal cast irons which varied in strength and hardness (designated GGG450, GGG600, and GGG700). Hemispherically tipped steel pins (designated 42CrMoS4/41CrS4) were used as the sliders. Except for the selection of the test duration, test procedures were similar to those described in ASTM Standard Test Method G133 for linearly reciprocating sliding. Among the three cast irons tested, the harder and stronger the alloy, the lower was its wear rate. Wear factors were approximately four orders of magnitude lower for experiments lubricated with fresh, fully formulated oil. There was a linear relationship between the Brinell hardness of the alloys and the negative logarithm of the wear factors that were expressed in mm3/N-m. Wear of lubricated test pins was not measurable due to the presence of deposits; however under non-lubricated sliding, the ratio of the wear of the flat specimen to that of the pin decreased as the hardness of the flat specimens approached that of the pin specimen.

Evaluation of high plutonia (44% PuO 2) MOX as a fuel for fast breeder test reactor

Uranium plutonium mixed oxide (MOX) containing up to 30% plutonia is the conventional fuel for liquid metal cooled fast breeder reactor (LMFBR). Use of high plutonia (>30%) MOX fuel in LMFBR had been of interest but not pursued. Of late, it has regained importance for faster disposition of plutonium and also for making compact fast reactors. Some of the issues of high plutonia MOX fuels which are of concern are its chemical compatibility with liquid sodium coolant, dimensional stability and low thermal conductivity. Available literature information for MOX fuel is limited to a plutonium content of 30%. Thermodynamic assessment of mixed oxide fuels indicate that with increasing plutonia oxygen potential of the fuel increases and the fuel become more prone to chemical attack by liquid sodium coolant in case of a clad breach. In the present investigation, some of these issues of MOX fuel have been studied to evaluate this fuel for its use in fast reactor. Extensive work on the out-of-pile thermo-physical properties and fuel-coolant chemical compatibility under different simulated reactor conditions has been carried out. Results of these studies were compared with the available literature information on low plutonia MOX fuel and critically analyzed to predict in reactor behaviour of this fuel containing 44% PuO 2. The results of these out-of-pile studies have been very encouraging and helped in arriving at a suitable and achievable fuel specification for utilization of this fuel in fast breeder test reactor (FBTR). As a first step of test pin irradiation programme in FBTR, eight subassemblies of the MOX fuel are undergoing irradiation in FBTR.