www.melanexjou.fora.pl

[loiwtjsf]

Provides a characteristic strength value and the lower yield point is slightly different: --- British standard steel export inspection by the problems encountered when


Production of deformed bar 99 different national standard under the yield point of steel with a yield strength of the provisions of a long time, we are determined to use the pointer to the next yield point of steel, the recent customer complaints related to the value of the people of the two large, up to 50MPa. To this end, we need to explore the differences between these two values. . L out to explain the concept. . Liu} Bs! 【Shu Qi Jiang J1.1 tensile test, 1j, although to a sample of a growing tension at both ends, so deformation, according to needs, or half-way stop continuous force until the relevant data, usually pulled to fracture. 1.2 during the test yield point, force does not increase when the sample is still able to Chung-long stress. 1.3 The yield on the yield point when the first drop occurred before the maximum stress,[link widoczny dla zalogowanych], the provisions of British Standard BS18 determine the last service point, the elastic stress rate, must meet the 180MPa/min ~ 1800MPa/min, and at a certain Rules fixed. l_4 plastic deformation under the yield under the yield point, excluding the initial transient phase when the effect of minimum stress. BS18 under the provisions of the yield point measured, the yield stage of plastic deformation strain rate must meet 0.015/min ~ 0.15/rain, and the stress rate of elastic deformation stage must meet 180MPa/min ~ 1800/rain. 1.5 provides the total strain characteristic strength (Proofstrenth) specimen gauge part of the total elongation (plastic plus elastic elongation elongation), the required percentage of the original stress gauge. For example, British Standard BS4449: 1988 provides the total elongation rate of 0.43 features of the stress intensity values for the requirement. BS18 provides that the provisions of characteristic strength measured value, the plastic deformation of the strain rate must be less than 015/rain, and the stress rate of elastic deformation stage must meet 180MPa/mln ~ 1800MPa/rain. 2 units of test equipment I 50T closed loop servo testing machine, is U.S. imports, with a three-channel servo control functions. The three channels are dis-placment control,[link widoczny dla zalogowanych], force control, strain control. The testing machine can be controlled according to certain rules of the force or strain the specimen elongation. Therefore,[link widoczny dla zalogowanych], test parameters can be set to meet the requirements of BS18, and test computer-controlled, almost no man-made factors. 3 test materials, process and results of the date of receipt of manuscripts: August 1998 10El Wuzhong division. Male. 34. Physical Test Engineer 2 1999 to take an 8m long 20MnSi, ~ 14 bar. Sample from which the interception of 10: five samples without making processing, five of 10 samples processed by standard sample requirements of British Standard RS4449 and BS18, were proud of 1O times the tensile test results shown in Table 1. Table 1 Test results chopsticks pieces' number of copper provides features △ db Diameter elastic stage M Ⅱ a yield strength MMDaM ∞ M ∞ MPa/rainMPa/min20Mn ● l44804l84l259620MnS】 ● l4480 {, 34051359832OMnS】 l44804】 842l6082OM + l4004424413859020M + l44804184ll59720Ml04804274l84l52OMnsi4104804234l64132OMnSl maggot 00 . O54gO4l340672OMnsi1O4Zl3974l320Mn ● 10005} 418 l1 △ d is to provide a characteristic strength with which poor, 6 to 10, the sample is processed into the 14-10 bare steel sample. Increased intensity of the reason is because the process to strengthen. Conclusion (1) provides that characteristic strength values are not equal to the lower yield point is slightly different between the two,[link widoczny dla zalogowanych], but the difference is not more than two values of a 11 to 13. To 460MPa as the base. Deviation of about 3. This is because the steel elastic modulus is about 2 × 10sMpa, the total strain of 0.43 (ie BS4449 provides a characteristic strength value) occurred in the yield of basic stage. From the stress-strain curves can illustrate this point. (2) In production testing, due to limitations of equipment conditions. Pointer method for general use under the yield point of steel. Because the production test in the testing machine used mostly for domestic open-loop testing machine, can only increase or decrease in oil, to control the stress rate qualitatively. However, due to the provisions of characteristic strength values and lower yield point or less, as long as the lower yield point of steel is slightly higher than the specified value (such as ≥ 480MPa), it certainly sets format for the goods, this approach is feasible. Cai Xiaoning, Tianze Hui,[link widoczny dla zalogowanych], Zeng Zhi-side participated in the test, hereby acknowledge

相关的主题文章：


[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]