关键词：阻尼；镓合金；铁；水利；磁致伸缩

查看摘要 索取原文[18页]

The development of cobalt alloys for the development of HIP implants has been evolving overtime. Accordingly, in this work an overview of the main microstructural factors that impact the mechanical properties, as well as the effect of interstitials such as carbon and nitrogen. In addition the role alloy pre-straining and heat treating on the amount of ε-martensite and on the exhibited mechanical properties is described. In general, it is shown that as the amount of ε-martensite exceeds 60 vol. percent, the alloy ductility is drastically reduced as the HCP phase becomes dominant in the matrix.

关键词：生物医学钴合金；植入物；ε-马氏体;医药制造业；力学性能

查看摘要 索取原文[14页]

We use x-ray spectroscopy and density functional theory to investigate the hydrogenation-induced electronic structure changes in graphene on Pt(111). The atom-specific properties of the spectroscopy allow for a direct projection of the band structure onto the carbon atoms; this was compared with the calculated density of states. Instead of the generally expected band opening behavior, we observe states at the Fermi level in the carbon-projected density of states. Hydrogenation is accompanied by pinning of the graphene to the substrate through the formation of local CPt bonds which cause the graphene layer to become metallic upon hydrogenation.

关键词：加氢；可逆；石墨烯

查看摘要 索取原文[19页]

The six important technical areas were selected by the workshop organizing committee, a group of experts from the auto and steel industries, and scientists from several National Laboratories. These selections were based on areas where there were known technical gaps, which if closed would have high impact on accelerating vehicle lightweighting with AHSS. The selected areas were: Steel Development, Fracture, Plasticity, Delayed Fracture/Hydrogen Embrittlement, Modulus Characterization and Joining. The main output of the workshop is contained within the breakout session reports, which summarize the technical requirements, engineering gaps and research needs. The breakout session reports are included below in the main workshop report.

关键词：钢铁；汽车；材料加工；车间；汽车燃料

查看摘要 索取原文[33页]

Directly-generated compressive residual stress has become a widely used surface modification technique. Intentional residual stress in solid materials can be produced by different surface compression methods. It is well known how residual stress field is influenced by the parameters of the shoot peening but only few articles address the phenomenon about the evolution of the stress during the operation of the machine component. The literature on residual stress decrease caused by fatigue load is scarce and the kinetics of this mechanism is not yet investigated. The present work reports on the examination of the effect of the fatigue load on compressive residual stress strengthened specimens. Investigations have been conducted at three stress levels. Residual stress data have been measured by X ray diffraction method before fatigue load and measurements have been repeated after defined fatigue cycles.

关键词：钢铁；残余应力；X射线衍射仪；疲劳

查看摘要 索取原文[10页]

The number of control loops used in process industry is growing continuously, whilst manpower is being reduced. Consequently even companies that have embraced new control technologies struggle to maintain satisfactory performance over the long term. Numerous investigations have shown that the performance of control systems in the process industries is not satisfactory, as mentioned in Chap. 1. This particularly applies for the steel industry, where it is the norm to perform controller tuning only at the commissioning stage and then never again. A loop that worked well at one time is prone to degradation over time unless regular check and maintenance is undertaken.

关键词：钢铁；回路；控制系统；调试

查看摘要 索取原文[38页]

This experiment examined the effect of accelerated corrosion testing and immersion testing on 13-mm-grade 10.9 bolts. A matrix containing chemical agent resistant coating (CARC) and bare Al 5059, as well as Rolled Homogeneous Armor (RHA) steel plates with CARC that are each bolted together with one bolt of each pretreatment system were subjected to GM9540P in an attempt to evaluate the corrosion prevention properties of each selected coating and pretreatment while simulating the practical applications of bolt-on armor. Five candidate finishes (zinc plating in accordance with the American Society for Testing and Materials ASTM)-B 633 with hexavalent chromium conversion coating as control were tested in replicate sets of assemblies. In the immersion phase of testing, each bath was heated to 75 F, and the salt solution was agitated in order to prevent stagnation and ensure equal heating. Testing was completed over 500 h, with visual and potential inspections at 1, 2, 4, 8, and 24 h, and every subsequent 24 h thereafter. Accelerated corrosion testing was programmed for 120 cycles GM9540 with inspection for corrosion creep at 20 cycle intervals. Corrosion creep in this experiment was defined visually as frosting for the onset of corrosion and red rust in the percentage of the fastener affected yielding separate observations. Each of the pretreatments are assessed and compared in terms of corrosion inhibition.

关键词：钢铁；螺栓；涂料；腐蚀；紧固件

查看摘要 索取原文[34页]

Accordingly, effective March 1, 2012, the Commission instituted countervailing duty investigation No. 701-TA-489 and antidumping duty investigation No. 731-TA-1201 (Preliminary). Notice of the institution of the Commissions investigations and of a public conference to be held in connection therewith was given by posting copies of the notice in the Office of the Secretary, U.S. International Trade Commission, Washington, DC, and by publishing the notice in the Federal Register of March 7, 2012 (77 FR 13631). The conference was held in Washington, DC, on March 22, 2012, and all persons who requested the opportunity were permitted to appear in person or by counsel.

关键词：钢铁；不锈钢；国际贸易；冲压不锈钢水槽

查看摘要 索取原文[120页]

In 2005 Focus: HOPE began working on a Technical Area Task to investigate advanced manufacturing in the area of Direct Deposition of Metal (DDM) for the Tank and Automotive Command (TACOM). In 2006, the scope was expanded to include basic research areas of Direct Deposition of Metal applicable to repairing military equipment and Focus: HOPE demonstrated the feasibility of conducting repairs on military equipment using Direct Deposition of Metal (Work Directive WD-FH-0001). The study also demonstrated that there could be a potential cost saving by repairing parts using DDM over purchasing new replacement parts. The overall project was extended in 2010 to provide additional time to conduct additional certification testing of repaired components and demonstrate the effectiveness of the parts repaired using Direct Deposition of Metal. For the present project, extensive studies were conducted on the metallurgical properties and bonding between the newly deposited metal and the parent metal substrate. The findings, results and conclusions of this process certification testing are provided in this report.

关键词：金属；军钢铁；弯曲；腐蚀；沉积零件

查看摘要 索取原文[39页]

Laser etched 300 series Stainless Steel Burst Disks (SSBD) ranging between 0.178 mm (0.007-in.) and 0.508mm (0.020-in.) thick were designed for use in a 17-caliber two-stage light gas launcher. First, a disk manufacturing method was selected using a combination of wire electrical discharge machining (EDM) to form the blank disks and laser etching to define the pedaling fracture pattern. Second, a replaceable insert was designed to go between the SSDB and the barrel. This insert reduced the stress concentration between the SSBD and the barrel, providing a place for the petals of the SSDB to open, and protecting the rifling on the inside of the barrel. Thereafter, a design of experiments was implemented to test and characterize the burst characteristics of SSBDs. Extensive hydrostatic burst testing of the SSBDs was performed to complete the design of experiments study with one-hundred and seven burst tests. The experiment simultaneously tested the effects of the following: two SSBD material states (full hard, annealed); five SSBD thicknesses 0.178, 0.254, 0.305, 0.381 mm (0.007, 0.010, 0.012, 0.015, 0.020-in.); two grain directions relative; number of times the laser etch pattern was repeated (varies between 5-200 times); two heat sink configurations (with and without heat sink); and, two barrel configurations (with and without insert). These tests resulted in the quantification of the relationship between SSBD thickness, laser etch parameters, and desired burst pressure. Of the factors investigated only thickness and number of laser etches were needed to develop a mathematical relationship predicting hydrostatic burst pressure of disks using the same barrel configuration. The fracture surfaces of two representative SSBD bursts were then investigated with a scanning electron microscope, one burst hydrostatically in a fixture and another dynamically in the launcher. The fracture analysis verified that both burst conditions resulted in a ductile overload failure indicated by transgranular microvoid coalescence, non-fragmenting rupture and mixed tensile and shear failure modes, regardless of the material states tested. More testing is underway to determine the relationship between SSBD burst pressure and projectile velocity.

关键词：钢铁;爆破试验;腐蚀;实验设计;激光;不锈钢

查看摘要 索取原文[47页]