原始组织对25MnV钢“零保温”淬火后组织性能的影响

采用正交组合回归设计试验方法,分别以淬火和热轧为预处理工艺,研究了不同原始组织条件下25MnV钢“零保温”淬火后的强度和硬度,并进行了组织分析.试验表明,经2次淬火,该钢得到极细的板条状马氏体组织,具有很高的强硬性,其性能优于热轧态“零保温”淬火.在较低温度“零保温”淬火时,原始组织对25MnV钢的强硬性影响显著,随淬火温度升高,其影响逐步减弱.通过低温“零保温”奥氏体逆相变淬火,可显著提高该钢的力学性能.     

“零保温”淬火温度对20 MnV 钢强度和硬度的影响

采用正交组合回归设计实验方法,研究了"零保温"淬火条件下,加热温度和回火温度对20 MnV钢强度和硬度的影响规律.试验结果表明,淬火温度对该钢的抗拉强度和硬度有显著影响,适当提高淬火温度,20 MnV钢"零保温"淬火的强硬性高于常规880℃淬火.     

原始组织对25MnV钢"零保温"淬火后组织性能的影响

采用正交组合回归设计试验方法,分别以淬火和热轧为预处理工艺,研究了不同原始组织条件下25MnV钢"零保温"淬火后的强度和硬度,并进行了组织分析.试验表明,经2次淬火,该钢得到极细的板条状马氏体组织,具有很高的强硬性,其性能优于热轧态"零保温"淬火.在较低温度"零保温"淬火时,原始组织对25MnV钢的强硬性影响显著,随淬火温度升高,其影响逐步减弱.通过低温"零保温"奥氏体逆相变淬火,可显著提高该钢的力学性能.     

45钢“零保温”淬火工艺的可行性研究

根据传热方程计算了45钢工件的透热时间,探讨了"零保温"淬火温度对钢的力学性能的影响.直径不大于70 mm的45钢工件,表面与心部达到840℃的时间相近;在780～900℃范围内随着淬火温度的升高,45钢的强度、硬度升高,经900℃"零保温"淬火后具有较高的强度和硬度;该钢"零保温"淬火后获得细小的板条状马氏体组织,其原因与奥氏体晶粒细化和奥氏体中碳分布不均匀有关.理论分析和实验结果表明45钢"零保温"淬火工艺是可行性的.     

新型低合金高强度Cr-Mo钢热处理工艺研究

本文对一种Cr-Mo系的低合金结构钢进行了研究,通过对该新型的射孔枪管用钢进行完全淬火,研究了淬火温度、保温时间和回火温度对实验钢组织和性能的影响。研究结果表明,钢的晶粒随淬火温度的升高而增大,硬度先增大后减小;在相同的淬火温度下,随着保温时间的延长,钢的硬度和晶粒度变化不大;回火温度升高,钢的硬度和强度逐渐降低,断面收缩率和冲击功逐渐增大。当淬火温度为900℃保温时间为40 min、回火温度为560℃保温时间为80 min时,钢的屈服强度达到927 MPa,大于130 ksi,硬度达到31.2 HRC,同时纵横冲击功分别达到了74.5 J和119.7 J的水平,综合性能最优。     

45钢淬火加热零保温可行性研究

对45钢在空气介质的箱式炉中进行淬火加热时，加热、保温时间能否缩短，特别是“零保温”是否可行等，进行了试验和研究。结果表明：工件心部到温即可淬火，对45钢制作的中小型工件在调质时，淬火加热过程的零保温是可行的，且零保温试样和经典加热试样的淬火组织与力学性能均无太大的差别。45钢淬火加热零保温可行性研究@白伟成     

45钢淬火加热零保温可行性研究

对４５钢在空气介质的箱式炉中进行淬火加热时，加热、保温时间能否缩短，特别是“零保温”是否可行等，进行了试验和研究。结果表明：工件心部到温即可淬火，对４５钢制作的中小型工件在调质时，淬火加热过程的零保温是可行的，且零保温试样和经典加热试样的淬火组织与力学性能均无太大的差别。     

60Si2Mn钢“零保温”淬火工艺的试验研究

本文通过对传统奥氏体化理论的详细分析，证明在这一理论指导下应用的淬火保温时间是保守的，不确切的，可以缩短为零，文中用６０Ｓｉ２Ｍｎ钢进行了“零保温和传统淬火工艺试验，将其淬火组织，奥氏体晶粒度和机械性能指标等进行对比，分析了６０Ｓｉ２Ｍｎ钢“零保温”淬火工艺的可行性。     

热处理工艺对20Mn2Cr汽车用钢热轧板组织和性能的影响

采用JMatPro软件模拟设计一种新型汽车用钢20Mn2Cr,利用Gleeble热模拟实验机对20Mn2Cr钢热轧板进行不同工艺的热处理,采用光学显微镜、扫描电子显微电镜、显微硬度计等分析冷却速度、等温淬火保温时间、奥氏体化温度对其组织和性能的影响。结果表明:20Mn2Cr钢淬透性良好,随着冷却速度的降低,组织中出现少量竹叶状的下贝氏体组织且原奥氏体晶粒增大,致使显微硬度降低;等温淬火保温时间对20Mn2Cr钢基体组织形貌影响不大,但随着保温时间的延长,显微硬度增加;当奥氏体化温度由单相区950℃调整到双相区800℃时,组织中出现少量铁素体组织,马氏体基体组织碳含量上升,致使显微硬度增大。     

退火工艺对低碳齿轮钢球化退火组织影响

通过对低碳20CrMnTiH齿轮钢在不同保温温度及保温时间进行直接淬火和球化退火试验,分析了退火温度及时间对齿轮钢球化退火组织及硬度的影响。     

热处理对34CrNi3Mo铸钢力学性能的影响

为研究不同热处理工艺对34CrNi3Mo铸钢力学性能的影响,对比了"喷水淬火+高温回火"、"油淬+高温回火"、"双液淬火(水-油)+高温回火"和"双液淬火(水-油)+两次高温回火"4种热处理工艺条件下34CrNi3Mo铸钢的力学性能。结果表明:采用"喷水淬火+高温回火"处理的试样不仅比"油淬+高温回火"处理的试样强度好、硬度高,而且塑性和冲击韧性也更好。当对铸件进行"双液淬火(水-油)+高温回火"后,可以实现铸件外强内韧的特性;双液淬火(水-油)后2次高温回火会使铸件的强度、硬度更高,但塑性、韧性下降。     

Effect of Quenching Parameters on Mechanical Property of Ultra High Strength Steel BR1500HS Based on Response Surface Methodology

Hot stamping of high strength steels is defined as a process in which blank is heated to the temperature of the austenite stabilization region for a definite time and then formed and quenched simultaneously in a mold with cooling channels. During this process, the processing parameters of austenite temperature and soaking time have strong effects on the mechanical properties such as quenching hardness, tensile strength and elongation. Hence, it is necessary to investigate the relationship between the mechanical properties and the two processing parameters. In this paper, the orthogonal experiment with two factors and five levels was applied, and the experimental data based on the orthogonal experiment was acquired. Based on the data, regression models were set up and the results of the analysis of variance （ANOVA） showed that it is reliable to predict the quenching hardness, tensile strength and elongation by the regression models. Besides, the optimal results of each single object were obtained based on response surface methodology （RSM）, and global optimums was gained by employing ideal point method in which the quenching hardness, and tensile strength and elongation were considered simultaneously.     

Effects of heat treatment on structures and properties of high speed steel rolls

The effects of quenching temperature, cooling pattern, temper temperature and temper times on the structure and properties of high speed steel (HSS) rolls have been investigated. The results show that, when the quenching temperature is lower than 1050℃ the hardness of HSS increases with the quenching temperature increasing in oil cooling, but when the quenching temperature exceeds 1100℃ the hardness decreases. In the conditions of salt bath cooling and air cooling, the effect of quenching temperature on the hardness is similar to the above law, but the quenching temperature obtaining the highest hardness is higher than that in oil cooling. When the temper temperature below 350℃ the hardness of HSS has a little change, when above 475℃ the hardness will increase with the temper temperature increasing, and the highest hardness is obtained at 525℃. When the temper temperature continues to increase, the hardness decreases. Twice temper has little effect on the hardness, but three times temper decreases the hardness. HSS in air cooling has lower hardenability, oil cooling can easily produce crackle, and HSS quenching in salt bath has high hardenability and excellent wear resistance.     

Effect of deep cryogenic treatment on the properties of 80CrMo12 5 tool steel

The effect of deep cryogenic treatment on the mechanical properties of 80CrMol2 5 tool steel was investigated.Moreover,the effects of stabilization (holding at room temperature for some periods before deep cryogenic treatment) and tempering before deep cryogenic treatment were studied.The results show that deep cryogenic treatment can eliminate the retained austenite,making a better carbide distribution and a higher carbide amount.As a result,a remarkable improvement in wear resistance of cryogenically treated specimens is observed.Moreover,the ultimate tensile strength increases,and the toughness of the sample decreases.It is also found that both stabilization and tempering before deep cryogenic treatment decrease the wear resistance,hardness,and carbides homogeneity compared to the deep cryogenically treated samples.It is concluded that deep cryogenic treatment should be performed without any delay on samples after quenching to reach the highest wear resistance and hardness.     

不同退火温度和冷却方式对铍青铜组织性能影响的研究

在国产QBe2.0退火试验中,确定了退火温度后,通过不同的保温温度进行处理,在保温到一定时间后出炉,经空冷至常温、水冷至常温两种方式对材料进行冷却,并对各种不同工艺下退火后的材料进行硬度、抗拉强度、延伸率等力学性能和显微组织的对比,分析得出了最佳的退火工艺,为将来的大规模生产做好准备.     

65MnV钢在塑料磨具顶杆中的应用

本通过对新材料65MnV进行力学性能、组织品粒度、冷加工性能、耐磨性等一系列试验，对实验结果深入分析．对比原塑料磨具整体淬火顶杆常用材料65Mn的力学性能和使用时的局限性，针对塑料磨具整体淬火顶杆的技术要求，确定65MnV具有更好的综合性能，可有效避免使用失效，提高使用寿命。     

模压工艺对CF+G/PEEK复合材料力学性能的影响

采用模压法制备了碳短纤维和石墨混合填充聚醚醚酮复合材料,以拉伸强度和冲击韧性作为力学性能评价指标,探讨和分析了制备工艺对CF+G/PEEK复合材料力学性能的影响,优化出了较佳的模压制备工艺参数。实验结果表明,较佳的模压制备工艺参数为:为加热温度390℃、保温时间20min、保压温度320℃、保压压力43MPa、保压时间15min。     

热处理对99.5Ge_(23)Se_(67)Sb_(10)-0.5CsCl玻璃组织和性能的影响

文中运用热处理的方法来提高99.5Ge23Se67Sb10-0.5CsCl红外玻璃的力学性能.采用XRD、SEM、FTIR和显微硬度计研究了热处理对99.5Ge23Se67Sb10-0.5CsCl玻璃组织和性能的影响.研究结果发现:当保温温度低于310℃时,随着保温时间的延长,99.5Ge23Se67Sb10-0.5CsCl材料析晶数目增多而尺寸变小,材料组织细化;红外透过率缓慢降低而硬度较好.当保温温度等于或高于310℃时,随着保温时间延长,材料内部晶粒粗大,透红外性能急剧变差且硬度变差.当玻璃在290℃下保温40h后,其维氏硬度可达2 121.49MPa,比热处理前提高了20%左右,并且红外透过率在8~12μm波段仍保持在60%以上.