The mechanical and tribological properties of polyetheretherketone （PEEK） composites filled with CaCO3 whisker in various content of 0～45% （wt pct） were investigated. The composite specimens were prepared by comp...The mechanical and tribological properties of polyetheretherketone （PEEK） composites filled with CaCO3 whisker in various content of 0～45% （wt pct） were investigated. The composite specimens were prepared by compression molding. Tribological testing of composites in dry wear mode against carbon steel ring was carried out on a MM200 block-on-ring apparatus. Data on neat PEEK were also included for comparison. It was observed that inclusion of CaCO3 whisker affected the most mechanical properties and the friction and wear in a beneficial way. With an increase in CaCO3 whisker content, friction coefficient continuously decreased but the trends in wear performance varied. The specific wear rate showed minima as 1.28×10^-6 mm^3/Nm for 25% CaCO3 whisker inclusion followed by a slow increase for further CaCO3 whisker addition. In terms of friction applications, when the tribological and mechanical properties are combined, the optimal content of CaCO3 whisker in the filled PEEK should be recommended as 15% to 20%. Fairly good correlations are observed in friction coefficient vs bending modulus and wear rate vs bending strength, confirming that the bending properties prove to be the most important tribology controlling parameters in the present work.展开更多
对摩擦性能优良的三嗪杂环进行水溶性改良,合成了一种无灰无磷水基润滑添加剂2,4,6-三(N,N-二羟乙基氨基亚甲基硫代)-均三嗪(SNOT),并用红外光谱仪对其结构进行分析。以自来水为基础液,采用四球摩擦磨损试验机考察了其在基础液中的摩擦...对摩擦性能优良的三嗪杂环进行水溶性改良,合成了一种无灰无磷水基润滑添加剂2,4,6-三(N,N-二羟乙基氨基亚甲基硫代)-均三嗪(SNOT),并用红外光谱仪对其结构进行分析。以自来水为基础液,采用四球摩擦磨损试验机考察了其在基础液中的摩擦学性能。结果表明,该添加剂能够较大程度地提高基础液的极压性能,并显著提高其抗磨减摩性能。通过磨斑表面的金相照片和 X 光能量色散谱(EDS)分析可知,在摩擦过程中,该添加剂与摩擦副表面发生了复杂的摩擦化学反应,在其表面生成硫、氮等复合边界润滑膜,从而起到极压抗磨减摩作用。展开更多
Six new 1,3,4-thiadiazole Schiff base derivatives were synthesized and characterized by IR spectroscopy and ~1H NMR spectrometry, and their anti-corrosion properties and thermal stability were investigated via thermog...Six new 1,3,4-thiadiazole Schiff base derivatives were synthesized and characterized by IR spectroscopy and ~1H NMR spectrometry, and their anti-corrosion properties and thermal stability were investigated via thermogravimetric analysis(TGA) and copper strip corrosion test. The tribological behavior of the said Schiff base derivatives was evaluated on an Optimol SRV~?4 oscillating reciprocating friction and wear tester. The worn surfaces of the steel discs were investigated using a scanning electron microscope(SEM) and energy dispersive X-ray spectrometer(EDS). The test results indicated that these thiadiazole Schiff base derivatives possessed favourable thermal stability, corrosion inhibiting ability and the capability of improving the tribological characteristic of the base oil effectively. It is assumed that the adsorbed additives probably reacted with the steel surfaces during the friction process, resulting in the formation of a protective film composed of sulphates, sulphides and organic nitrogen compounds.展开更多
Micro-arc oxidation is a recently developed surface treatment technology under anodic oxidation. Through micro-arc oxidation, a ceramic coating is directly formed on the surface of magnesium alloy, by which its surfac...Micro-arc oxidation is a recently developed surface treatment technology under anodic oxidation. Through micro-arc oxidation, a ceramic coating is directly formed on the surface of magnesium alloy, by which its surface property is significantly improved. In this paper, a dense ceramic oxide coating was prepared on an AZ31 magnesium alloy by micro-arc oxidation in a NaOH-Na2SiO3-NaB407-（NaPO3）6 electrolytic solution. Micro-structure, surface morphology and phase composition were analysed using scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The tribological behavior of the micro-arc oxidation ceramic coating under dry sliding against GCr15 steel was evaluated on a ball-on-disc test rig. The results showed that the AZ31 alloy was characterized by adhesion wear and scuffing under dry sliding against the steel, while the surface micro-arc oxidation ceramic coating experienced much abated adhesion wear and scuffing under the same testing conditions. The micro-arc oxidation ceramic coating showed good friction-reducing and fair antiwear ability in dry sliding against the steel.展开更多
文摘The mechanical and tribological properties of polyetheretherketone （PEEK） composites filled with CaCO3 whisker in various content of 0～45% （wt pct） were investigated. The composite specimens were prepared by compression molding. Tribological testing of composites in dry wear mode against carbon steel ring was carried out on a MM200 block-on-ring apparatus. Data on neat PEEK were also included for comparison. It was observed that inclusion of CaCO3 whisker affected the most mechanical properties and the friction and wear in a beneficial way. With an increase in CaCO3 whisker content, friction coefficient continuously decreased but the trends in wear performance varied. The specific wear rate showed minima as 1.28×10^-6 mm^3/Nm for 25% CaCO3 whisker inclusion followed by a slow increase for further CaCO3 whisker addition. In terms of friction applications, when the tribological and mechanical properties are combined, the optimal content of CaCO3 whisker in the filled PEEK should be recommended as 15% to 20%. Fairly good correlations are observed in friction coefficient vs bending modulus and wear rate vs bending strength, confirming that the bending properties prove to be the most important tribology controlling parameters in the present work.
文摘对摩擦性能优良的三嗪杂环进行水溶性改良,合成了一种无灰无磷水基润滑添加剂2,4,6-三(N,N-二羟乙基氨基亚甲基硫代)-均三嗪(SNOT),并用红外光谱仪对其结构进行分析。以自来水为基础液,采用四球摩擦磨损试验机考察了其在基础液中的摩擦学性能。结果表明,该添加剂能够较大程度地提高基础液的极压性能,并显著提高其抗磨减摩性能。通过磨斑表面的金相照片和 X 光能量色散谱(EDS)分析可知,在摩擦过程中,该添加剂与摩擦副表面发生了复杂的摩擦化学反应,在其表面生成硫、氮等复合边界润滑膜,从而起到极压抗磨减摩作用。
文摘Six new 1,3,4-thiadiazole Schiff base derivatives were synthesized and characterized by IR spectroscopy and ~1H NMR spectrometry, and their anti-corrosion properties and thermal stability were investigated via thermogravimetric analysis(TGA) and copper strip corrosion test. The tribological behavior of the said Schiff base derivatives was evaluated on an Optimol SRV~?4 oscillating reciprocating friction and wear tester. The worn surfaces of the steel discs were investigated using a scanning electron microscope(SEM) and energy dispersive X-ray spectrometer(EDS). The test results indicated that these thiadiazole Schiff base derivatives possessed favourable thermal stability, corrosion inhibiting ability and the capability of improving the tribological characteristic of the base oil effectively. It is assumed that the adsorbed additives probably reacted with the steel surfaces during the friction process, resulting in the formation of a protective film composed of sulphates, sulphides and organic nitrogen compounds.
基金supported by Scientific Research Common Program of Beijing Municipal Commission of Education (No.KM200510017005)Beijing Excellent Talent Nurture and Sponsor Project(20061D0500500151)
文摘Micro-arc oxidation is a recently developed surface treatment technology under anodic oxidation. Through micro-arc oxidation, a ceramic coating is directly formed on the surface of magnesium alloy, by which its surface property is significantly improved. In this paper, a dense ceramic oxide coating was prepared on an AZ31 magnesium alloy by micro-arc oxidation in a NaOH-Na2SiO3-NaB407-（NaPO3）6 electrolytic solution. Micro-structure, surface morphology and phase composition were analysed using scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The tribological behavior of the micro-arc oxidation ceramic coating under dry sliding against GCr15 steel was evaluated on a ball-on-disc test rig. The results showed that the AZ31 alloy was characterized by adhesion wear and scuffing under dry sliding against the steel, while the surface micro-arc oxidation ceramic coating experienced much abated adhesion wear and scuffing under the same testing conditions. The micro-arc oxidation ceramic coating showed good friction-reducing and fair antiwear ability in dry sliding against the steel.
