强力喷丸对提高碳氮共渗齿轮接触疲劳强度的研究

通过对碳氮共渗齿轮试片进行了多次强力喷丸试验．研究了不同喷丸参数下的强力喷丸的效果及喷丸后的低温回火处理对提高齿轮试片表面接触疲劳强度的影响。为强力喷丸工艺更好地应用于工业生产提供了一些参考。     

齿轮强化喷丸在岸边集装箱起重机齿轮箱中的应用

以岸桥集装箱起重机齿轮箱中各级齿轮为研究对象,介绍了一种利用高频疲劳试验机,对喷丸和未喷丸渗碳淬火齿轮做脉动试验的方法,得出各试验齿轮的弯曲疲劳强度及存活率、应力、寿命曲线,通过弯曲疲劳强度试验对比,以验证实施强化喷丸处理。     

20CrMnMo齿轮弯曲疲劳性能试验研究

将同一批次加工的20CrMnMo齿轮分为两组,其中一组经过齿根喷丸强化后,分别对两组齿轮进行弯曲疲劳强度试验,通过对试验数据的处理,获得两组齿轮的R-S-N曲线和不同可靠度的极限应力,为后续齿轮设计制造提供了必要的试验数据。     

某变速箱齿轮断齿分析

通过对失效齿轮的断口分析发现齿轮断齿属于疲劳断裂,从设计、装配、材料热处理以及零件质量方面综合排查得出,齿轮喷丸覆盖率不足是导致齿轮疲劳断裂的主要原因,针对该原因,按照要求的SAE AMS-S-13165喷丸技术规范,对零件进行重新喷丸,弥补所缺少的喷丸覆盖率,使齿轮疲劳强度有了明显提高,并通过台架耐久试验,有效地解决了试验中的断齿问题。     

喷丸强化对不锈钢弹簧疲劳性能的影响

本文介绍喷丸强化对不锈钢压缩弹簧疲劳强度的影响。通过试验证明,喷丸工艺对疲劳性能影响很大。应用最佳喷丸参数,能最大限度提高疲劳强度。本文所列图表和数据均为实际试验结果,可供设计和工艺人员参考。     

硬喷丸强化对提高渗碳齿轮疲劳强度的研究

通过对渗碳齿轮试片进行多次对比硬喷丸试验，揭示了硬喷丸强化效果与材料、喷丸工艺参数及热处理间的影响关系，为硬喷丸工艺更好地应用于工业生产提供了较好的方案。     

喷丸强化工艺在装载机驱动桥弧齿锥齿轮上的应用

本文介绍了验证弧齿锥齿轮强化喷丸技术的过程,通过对某型号装载机产品驱动桥的弧齿锥齿轮副的失效原因分析,确定轮齿的弯曲疲劳强度不足,采用强化喷丸工艺,经过台架及整机可靠性试验等过程,提升强度及寿命,达到预期效果。对提高齿轮强度及寿命有一定的借鉴作用。     

工程机械螺旋锥齿轮喷丸强化工艺及试验研究

通过对装载机驱动桥螺旋锥齿轮样件进行喷丸强化试验,研究了该齿轮齿面及齿根的喷丸强化效果,找出喷丸工艺参数中对喷丸效果影响显著的参数,寻求合理的喷丸强化工艺参数组合。通过模拟重载工况,在恒定扭矩及转速条件下进行加速疲劳台架试验,验证喷丸强化工艺可提高螺旋锥齿轮的疲劳寿命。在不改变齿轮设计结构的情况下,从工艺角度提高齿轮强度,减少设计成本,为喷丸强化工艺应用于工业生产奠定基础。     

高强度传动系齿轮的开发

一种用于前轮驱动、末级传动装置的高强度齿轮已被开发出来，这种齿轮所用钢材的钼元素含量较高，以便使渗碳后所保持的奥氏体可能比铬钢多。因此，它能承受较硬钢丸的强力喷丸处理。钢丸颗粒的发射是借助于一个压缩空气－－喷嘴系统实施的，用这种方法处理的齿轮，其疲劳强度比通常的齿轮要高1．6倍以上。     

渗碳齿轮钢喷丸强化工艺试验研究

针对渗碳齿轮钢齿轮进行了喷丸强化试验,研究了该齿轮齿面及齿根的喷丸强化效果,找出不同的喷丸工艺参数中对喷丸表面粗糙度影响的因素和参数,寻求合理的喷丸强化工艺参数组合,为其他零件喷丸强化应用提供指导。     

喷丸强化在新能源汽车轴齿上的应用

针对某新能源输入轴上仿真安全因子偏低的齿轮进行喷丸强化,结合其喷丸强化重点区域进行了有效的工装和喷丸饱和曲线工艺设计。同时,对喷丸后的齿面粗糙度以及规定位置进行了残余应力测试。喷丸后的输入轴应力合格及满足整车耐久测试要求,确认合理的喷丸能有效改善轴齿的应力状态,提高其弯曲和接触安全系数。     

Surface durability of powder-forged roller treated by shot peening

To investigate the influence of shot peening on the surface durability of powder-forged rollers, the case-hardened powder-forged rollers with a forging density of 7.5 g/cm³ treated by the single shot peening and the double shot peening were fatigue-tested under a sliding-rolling contact condition. The surface roughness, the surface hardness and the surface compressive residual stress of the rollers were increased by the shot peening. In addition, the pores near the roller surface were deformed by the shot peening. The failure mode of all the test rollers was spalling due to subsurface cracking. The fatigue lives of all the test rollers were improved by the shot peening, and that of the test roller S08, which was shot-peened with the hardest steel shots in this experimental range, was especially improved. The surface durability of the test roller S08 was also most improved by the shot peening. Cracks became difficult to occur and propagate under the roller surface since the pores near the roller surface were deformed by the stronger shot peening. In this study, double shot peening, which generally restrains the increase in surface roughness, was not particularly effective for the improvement in the surface durability of the powder-forged rollers, because the influence of tangential force on fatigue was not always great in a case of subsurface cracking.     

高强度钢喷丸强化处理的试验研究

喷丸强化是一种以小而硬的弹丸连续高速撞击金属零件表面而进行的一种特殊加工方法,零件通过喷丸可以大大提高材料的疲劳性能和抵抗应力腐蚀的能力。针对某型飞机上的喷丸强化零件,选取材料牌号为16Co14Ni10Cr2Mo高强度钢为研究对象,对两种厚度的试样进行不同喷丸强度的喷丸强化,对不同喷丸强度的试样进行疲劳寿命和残余应力场对比分析。     

TiB_2/Al复合材料喷丸后微区残余应力的有限元模拟

采用ANSYS/LS-DYNA有限元分析软件建立了颗粒增强TiB2/Al复合材料的喷丸模型,并对喷丸后残余应力分布进行了预测;然后对复合材料进行了喷丸试验,对残余应力进行了检测;将试验结果与模拟结果进行了对比。结果表明:该复合材料喷丸后残余应力分布的试验结果与模拟结果基本相符;喷丸后最表层部分增强体呈拉应力状态,在材料残余压应力场内,由于增强体和基体材料力学性能的差异,增强体的残余应力值普遍大于基体中的。     

喷丸强化残余应力对疲劳性能和变形控制影响研究进展

作为机械表面强化技术之一,喷丸强化使工件表层发生形变硬化,引入较高的残余压应力,减少了疲劳应力作用下微裂纹的萌生并抑制其扩展,从而显著提高零件的抗疲劳断裂和抗应力腐蚀开裂的能力。基于喷丸残余应力解析计算模型,从余弦函数模型、接触应力模型和球腔膨胀模型三个方面介绍喷丸强化残余应力的产生,进而对喷丸残余应力的仿真预测及影响规律进行论述。为了提高试件疲劳强度而引入的残余压应力会带来影响形位精度的变形,基于此阐述了喷丸残余应力对疲劳性能的影响及其在疲劳过程中的演化,同时论述了喷丸残余应力变形预测及控制的研究现状,最后对喷丸残余应力未来的研究内容与发展方向进行展望。     

Investigation of fatigue properties of shot peened and plasma nitrocarburized P/M FC0205 steel

One of the widely used powder metal materials in automotive industry, which is copper steel FC 0205 (Fe + 2% Cu + 0.5% C), was used in this study. The pressed samples has been prepared at the compression pressure of 680 MPa and sintered in conventional furnace at 1120°C for 30 minutes. The samples with 7 Mg/m³ densities were used as fatigue and shot peening processes. Shot peening were applied with 20A and 32A and the others were not peened. Plasma nitrocarburizing process was performed at 555°C for 2 hours under 600–900 Pa pressure. Fatigue tests were conducted at room temperature on a rotating bending type fatigue test device. It was determined that shot peening should be used where increased fatigue strength is needed, and plasma nitrocarburizing should be preferred where surface hardness is required, and plasma nitrocarburizing after shot peening process is much more useful.     

激光冲击强化与喷丸提高不锈钢疲劳性能对比研究

对不锈钢材料1Cr11Ni2W2MoV进行了激光冲击强化和喷丸强化后表面粗糙度和残余应力测试分析,与喷丸相比,激光冲击强化对试件表面形貌和表面粗糙度的影响更小,产生的残余压应力更大。对光滑试件和2种强化后试件的振动疲劳对比试验表明,激光冲击强化能显著提高不锈钢材料振动疲劳寿命,是喷丸的2倍以上。     

Effect of surface treatments on the strength of carburized gears

This paper deals with effects of surface treatment on the bending fatigue strength of SCM415 carburized spur gears. The test gears are treated by the combination of shot peening, chemical polishing and electropolishing after carburization. The fatigue tests demonstrate that the strength is sensitive to the surface condition of tooth fillet and the removal of the nonmartensitic layer caused by decarburization is considerably effective in enhancing the strength. In the first part of this paper, the influence of surface treatments such as shot peening, chemical polishing and electropolishing on the strength enbancement for carburized gears are summarized and discussed. In the second part, the crack lengths are calculated from the fatigue test results for the carburized and surface-treated gears, and the effect of surface treatments is discussed from the view point of fracture mechanics.     

Effect of shot peening coverage on fatigue limit in round bar of annealed medium carbon steel

Shot peening is an effective and economical technique for improving the fatigue strength of metallic components by inducing compressive residual stress and hardening the layer near the surface. The effect is generally evaluated by main two parameters: coverage and peening intensity. However, the valuable coverage for improving the fatigue strength depends on the shape of the target material. In this study, the effect of coverage on fatigue limit in round bar of annealed medium carbon steel was experimentally studied. The fatigue limits for shot peened round bar specimens with 140–2300% coverage increased 14–25% by comparing those for non-peened round bar specimens. The valuable range of coverage was 280–60% in the used material and shot peening condition for improving the fatigue limit in short time. The result indicates that the valuable coverage of the round bar material is higher than full coverage to improve the fatigue limit of the material due to the effect of incident angle on round bar, even though the degree depends on the materials and shot peening conditions.