40crnimo棒料-40crnimoA價格//江蘇40crnimo棒料-40crnimoA價格

蘇州倍徠斯特殊鋼事業部主要加工銷售進口國產寶鋼、東北特鋼(撫順特鋼)、長鋼、首鋼、馬鋼、沙鋼、杭鋼、南鋼,以及進口鋼廠德國蒂森克虜伯鋼鐵、韓國浦項鋼鐵、德國撒斯特、日本新日制鐵、美國鋼鐵、日本大同/日立、美國芬可樂、奧地利百祿、瑞典一勝百等各大著名鋼廠的優質鋼材,長期大量供應現貨：
碳素結構鋼Q235、Q345(A/B/C/D),SS300,S185等;
優質碳素結構鋼65Mn,C10E,等;低合金高強度結構鋼Q295,S690Q,550,等;
合金結構鋼cr、mn、crmo、crmn、crni、crnimo、crmov、crmnmo、crmnsi、crnimov等系列合金鋼：20cr~40cr、12~15crmo、20crmo、30crmo、35crmo、40~42crmo，42crmo4、20crmo4、4140、4118、4135、SCM415、SCM420、SCM430、SCM435、SCM440、12crmov、12cr1mov、35crmov、25cr2mov、25cr2mo1v、38crmoal、21crmov5-7、31crmov9、SACM645、41cralmo7、15crmn、20crmn、16mncr5、20mncr5、20crmnti、30crmnsi、35crmnsi、20crmnmo、40crmnmo、30crmnti、20crni、40crni、45~50crni、12crni2、12crni3、14nicr14、14nicr10、SNC415、SNC815、20crni3、30crni3、SNC631、37crni3、SNC836、15nicr13、12cr2ni4、20cr2ni4A、3316、3325、8640、4720、14nicr18、20crni2mo、sae4320、SNCM420、SNCM220、20crnimo、SAE8620H、aisi4340、SNCM439、40crni2mo、40crnimo、36crnimo4、34crnimo6、36crnimo16、40crnimo6、45crnimov、18cr2ni4wA、25cr2ni4wA、SAE8720等
易切削鋼Y12、Y12Pb、Y15、Y15Pb、12L14、1215，9smn28、9smn28K、11smn30、Y40mn、Y20,等;
彈簧鋼65Mn,60si2mn、60si2cr、SUP7SUP2,SUP10,6150等;
軸承鋼Gcr15、G20crnimo、Gcr18、Gcr18mo、100Cr6,52100,9Cr18Mo等;
合金工具鋼9SiCr,3cr2w8v、SKD11,SKD61、4crw2si、5crw2si、6crw2si、9cr2mo、9cr2、cr12、
cr12mov、5crnimo、90sicr5、3cr2mo、3cr2nimo、H13、SKD5、5crmnmo等;
碳素工具鋼SM55,S45C,T7A、T8A、T8Mn，T10A,SM45,SM48等;
高速工具鋼6542,W18cr4v、YXR3、YXM1、ASP2023、T4,SKH2,T15等。

40CrNiMo鋼齒輪軸斷裂原因分析
 摘要：通過化學成分分析、力學性能測試、光學顯微鏡分析、掃描電鏡和X射線能譜儀，對40CrNiMo鋼齒輪軸斷裂原因進行分析。失效分析結果表明，齒輪軸斷裂為疲勞斷裂，調質熱處理不當及機加工缺陷是齒輪軸斷裂的主要原因。關鍵詞：40CrNiMo鋼齒輪軸；失效分析；疲勞斷裂；中圖分類號：TG162.71 文獻標識碼：A

前言 某企業齒輪軸在使用較短時間后發生突然斷裂，該軸是齒輪軸，斷裂位置為齒輪軸大小直徑的臺階處。在斷裂過程中，齒輪軸一直在轉動，所以斷面被嚴重磨損和污染，接受樣品時表面已經銹蝕，如圖1所示。該軸的材質為40CrNiMo
鋼，熱處理狀態為調質處理。

2理化檢驗 2.1化學成分 對斷裂齒輪軸取樣進行化學成分分析，檢測結果表明，該軸的化學成分符合GB/T3077-1999標準中的對40CrNiMo鋼的技術要求，如表1所示。說明軸的材質符合規定。 表140CrNiMo鋼齒輪軸的化學成分（wt%）
Table
1Chemicalcompositionof40CrNiMosteelgearshaft（wt%）
項目    C    Si   Mn     Mo     P       S    Cu      Cr      Ni
實測值0.41  0.24  0.62  0.18  0.018  0.0048   0.20   0.71    1.36
標準值 0.37-0.44 0.17-0.37 0.50-0.80 0.15-0.25 ≤0.025 ≤0.025 ≤0.25 0.60-0.90 1.25-1.65

40NiCrMo鋼是典型的調質鋼，因其回火索氏體組織具有良好的強度、硬度、塑性、韌性而廣泛用于軸類零件。斷裂齒輪軸的化學成分符合標準GB/T3077-1999的要求，低倍組織觀察未發現明顯的中心疏松、一般疏松、偏析、一般點狀偏析、皮下氣泡、晶間裂紋，夾雜物評定結果合格。硬度檢測結果表明，試樣的表層硬度低于內部。齒輪軸內部碳含量高，外表面碳含量低，致使硬度值中心高、表面低。標準要求該軸的硬度小于269，而檢測的幾個點平均后的硬度值為282，高于標準要求。硬度偏高的原因可能是調質處理的回火溫度偏低或保溫之間過短。拉伸檢測結果表明，齒輪軸的抗拉強度、屈服強度低于標準要求，原因可能是淬火過程中，沒有得到盡可能多的馬氏體組織。斷面收縮率和沖擊吸收能量偏小表明材料的塑性、韌性較差。 綜上，在拉伸、硬度和沖擊等性能的結果中，只有斷后伸長率一項是合格的。由于該軸材質符合標準，力學性能不合格主要是由熱處理不當引起。齒輪軸斷面有裂紋源區、疲勞裂紋擴展區和瞬斷區3個明顯區域，屬于典型的疲勞斷裂。瞬斷區約占斷裂面60%，較大的瞬斷區說明軸在服役中承受較大的拉應力。機加工淺槽臺階處的不規則的機加工缺陷則容易產生應力集中，觸發早期裂紋。

Fracture analysis of 40CrNiMo steel gear shaft
Abstract: by chemical composition analysis, mechanical property test, optical microscope analysis, scanning electron microscope and X ray energy spectrometer, the causes of the fracture of 40CrNiMo steel were analyzed. Failure analysis shows that the fracture of the gear shaft is fatigue fracture, and the improper quenching and tempering heat treatment is the main cause of the fracture of the gear shaft. Key words: 40CrNiMo steel gear wheel axle; failure analysis; fatigue fracture; TG162.71
The gear shaft of the enterprise is suddenly broken after a short period of time, which is the gear shaft and the position of the fracture position is the diameter of the gear shaft. In the course of the fracture, the gear shaft is rotating, so the cross section is badly worn and polluted, and the surface of the sample has been corroded, as shown in Figure 1. The material of the shaft is 40CrNiMo
Steel, heat treatment state for conditioning treatment.
Chemical composition analysis of the chemical composition of the fractured gear shaft was carried out in 2 chemical test 2.1 chemical components. The results show that the chemical composition of the shaft is in accordance with the technical requirements of the 40CrNiMo standard, as shown in Table 1. The material of the shaft is in accordance with the regulations. Table 140CrNiMo chemical composition (wt%) of the steel tooth wheel axle
Table
1Chemicalcompositionof40CrNiMosteelgearshaft (wt%)
Item Si Mn Mo P S Cu Cr Ni C
Measured value 0.24 0.62 0.18 0.018 0.0048 0.71 1.36 0.20
The standard value of 0.37-0.44 0.17-0.37 0.50-0.80 0.15-0.25 = 0.025 0.60-0.90 1.25-1.65 = 0.025 = 0.25
40NiCrMo steel is a typical quenched and tempered steel, because of its high strength, hardness, plasticity, toughness and widely used in the shaft parts. The chemical composition of the fractured gear shaft meets the requirements of the standard GB/T3077-1999, and the low magnification observation has not found obvious central porosity, general porosity, segregation, general segregation, subcutaneous bubble, intergranular crack, inclusion assessment results are qualified. Hardness test results show that the surface hardness of the specimen is lower than that of the sample. The internal carbon content of the gear shaft is high, the external surface carbon content is low, resulting in the high hardness value center, the surface is low. The hardness of the shaft is less than 269, and the average hardness of the shaft is 282, which is higher than the standard. The reason of the high hardness of the high temperature and low temperature or heat preservation is the reason of the high hardness. Tensile test results show that the tensile strength and yield strength of the gear shaft are lower than the standard. The reason may be that the quenching process is not as much as possible. Section shrinkage ratio and impact energy of the impact of the small to show that the material is plastic, toughness is poor. In summary, the tensile, hardness and impact properties of the results, only the elongation is a qualified. As the shaft material is in conformity with the standard, the mechanical properties of the material are mainly caused by improper heat treatment. There are 3 distinct regions of the crack source area, the fatigue crack propagation zone and the transient zone in the gear shaft section, which are typical fatigue fracture. The transient zone is about 60% of the fracture surface, and the larger the stress of the shaft is in the service. The machining of the irregular machine with the shallow slot of the machine is easy to produce the stress concentration, and the early crack is triggered.