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  12Cr1MoVG合金彎(wan)頭質的硬度標(biao)準(zhun)值(zhi)

  合(he)(he)金(jin)(jin)管(guan)件，12Cr1MoVG合(he)(he)金(jin)(jin)彎頭(tou)(tou)質的(de)硬(ying)(ying)(ying)度(du)(du)(du)標準值(zhi)，12Cr1MoVG合(he)(he)金(jin)(jin)彎頭(tou)(tou)金(jin)(jin)屬材(cai)料(liao)抵(di)抗(kang)硬(ying)(ying)(ying)的(de)物體(ti)壓陷(xian)表面的(de)能力，稱為硬(ying)(ying)(ying)度(du)(du)(du)。12Cr1MoVG合(he)(he)金(jin)(jin)彎頭(tou)(tou)的(de)根據試驗方法和適用(yong)范(fan)圍不(bu)同，硬(ying)(ying)(ying)度(du)(du)(du)又可分為布氏(shi)硬(ying)(ying)(ying)度(du)(du)(du)、洛氏(shi)硬(ying)(ying)(ying)度(du)(du)(du)、維(wei)氏(shi)硬(ying)(ying)(ying)度(du)(du)(du)、肖氏(shi)硬(ying)(ying)(ying)度(du)(du)(du)、顯(xian)微硬(ying)(ying)(ying)度(du)(du)(du)和高溫硬(ying)(ying)(ying)度(du)(du)(du)等。對于12Cr1MoVG合(he)(he)金(jin)(jin)彎頭(tou)(tou)一般常用(yong)的(de)有布氏(shi)、洛氏(shi)、維(wei)氏(shi)硬(ying)(ying)(ying)度(du)(du)(du)三種。  

  合(he)(he)(he)金(jin)(jin)管件布(bu)氏(shi)(shi)(shi)硬(ying)度(du)（HB 用一定直(zhi)(zhi)(zhi)徑(jing)的鋼(gang)(gang)(gang)球(qiu)或(huo)硬(ying)質合(he)(he)(he)金(jin)(jin)球(qiu)，以(yi)規定的試(shi)(shi)(shi)驗(yan)(yan)力(li)（F）壓入(ru)式樣表(biao)面(mian)，經規定保持(chi)時間后卸(xie)除試(shi)(shi)(shi)驗(yan)(yan)力(li)，測量(liang)試(shi)(shi)(shi)樣表(biao)面(mian)的壓痕(hen)(hen)直(zhi)(zhi)(zhi)徑(jing)（L）布(bu)氏(shi)(shi)(shi)硬(ying)度(du)值是以(yi)試(shi)(shi)(shi)驗(yan)(yan)力(li)除以(yi)壓痕(hen)(hen)球(qiu)形表(biao)面(mian)積所得的商(shang)。以(yi)HBS（鋼(gang)(gang)(gang)球(qiu)）表(biao)示，單位(wei)為(wei)N/mm2(MPa 其計(ji)算公式為(wei) 式中：F--壓入(ru)金(jin)(jin)屬試(shi)(shi)(shi)樣表(biao)面(mian)的試(shi)(shi)(shi)驗(yan)(yan)力(li)，N； D--試(shi)(shi)(shi)驗(yan)(yan)用鋼(gang)(gang)(gang)球(qiu)直(zhi)(zhi)(zhi)徑(jing)，mm d--壓痕(hen)(hen)平均直(zhi)(zhi)(zhi)徑(jing)，mm。 測定布(bu)氏(shi)(shi)(shi)硬(ying)度(du)較準確可靠，但一般HBS只適用于(yu)(yu)450N/mm2（MPa）以(yi)下的金(jin)(jin)屬材料，對(dui)于(yu)(yu)較硬(ying)的鋼(gang)(gang)(gang)或(huo)較薄的板(ban)材不適用。在12Cr1MoVG合(he)(he)(he)金(jin)(jin)管標準中，12Cr1MoVG合(he)(he)(he)金(jin)(jin)管布(bu)氏(shi)(shi)(shi)硬(ying)度(du)用途最廣，往往以(yi)壓痕(hen)(hen)直(zhi)(zhi)(zhi)徑(jing)d來表(biao)示該(gai)材料的硬(ying)度(du)，既(ji)直(zhi)(zhi)(zhi)觀，又方(fang)便。合(he)(he)(he)金(jin)(jin)三通舉例：120HBS10/1000130：表(biao)示用直(zhi)(zhi)(zhi)徑(jing)10mm鋼(gang)(gang)(gang)球(qiu)在1000Kgf（9.807KN）試(shi)(shi)(shi)驗(yan)(yan)力(li)作用下，保持(chi)30s（秒）測得的布(bu)氏(shi)(shi)(shi)硬(ying)度(du)值為(wei)120N/ mm2（MPa）

  合(he)(he)金(jin)(jin)管(guan)件洛(luo)(luo)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)（HK）洛(luo)(luo)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)試(shi)(shi)驗(yan)(yan)(yan)同(tong)布(bu)(bu)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)試(shi)(shi)驗(yan)(yan)(yan)一(yi)樣(yang)，12Cr1MoVG合(he)(he)金(jin)(jin)管(guan)都(dou)是(shi)(shi)(shi)壓痕試(shi)(shi)驗(yan)(yan)(yan)方(fang)法(fa)(fa)。不同(tong)的(de)(de)是(shi)(shi)(shi)，它是(shi)(shi)(shi)測(ce)量(liang)(liang)(liang)壓痕的(de)(de)深度(du)(du)(du)(du)(du)(du)。即(ji)(ji)，在(zai)初邕試(shi)(shi)驗(yan)(yan)(yan)力(li)（Fo）及總試(shi)(shi)驗(yan)(yan)(yan)力(li)（F）的(de)(de)先后作(zuo)用(yong)(yong)(yong)下，將壓頭(tou)（金(jin)(jin)鋼廠圓錐(zhui)(zhui)體或鋼球）壓入試(shi)(shi)樣(yang)表(biao)(biao)面，經規(gui)定(ding)(ding)保持(chi)時間(jian)后，卸(xie)除主試(shi)(shi)驗(yan)(yan)(yan)力(li)，用(yong)(yong)(yong)測(ce)量(liang)(liang)(liang)的(de)(de)殘余壓痕深度(du)(du)(du)(du)(du)(du)增(zeng)量(liang)(liang)(liang)（e）計算(suan)硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)值(zhi)其(qi)12Cr1MoVG合(he)(he)金(jin)(jin)管(guan)值(zhi)是(shi)(shi)(shi)個(ge)(ge)(ge)無名數，以符號HR表(biao)(biao)示，所用(yong)(yong)(yong)標(biao)尺(chi)有A、B、C、D、E、F、G、H、K等(deng)9個(ge)(ge)(ge)標(biao)尺(chi)。其(qi)中(zhong)常用(yong)(yong)(yong)于(yu)(yu)鋼材硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)試(shi)(shi)驗(yan)(yan)(yan)的(de)(de)標(biao)尺(chi)一(yi)般為(wei)A、B、C，即(ji)(ji)HRA、HRB、HRC。硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)值(zhi)用(yong)(yong)(yong)下式計算(suan)： 當用(yong)(yong)(yong)A和C標(biao)尺(chi)試(shi)(shi)驗(yan)(yan)(yan)時，HR=100-e 當用(yong)(yong)(yong)B標(biao)尺(chi)試(shi)(shi)驗(yan)(yan)(yan)時，HR=130-e 式中(zhong)e--殘余壓痕深度(du)(du)(du)(du)(du)(du)增(zeng)量(liang)(liang)(liang)，其(qi)什(shen)系以規(gui)定(ding)(ding)單(dan)(dan)位0.002mm表(biao)(biao)示，即(ji)(ji)當壓頭(tou)軸向(xiang)位移(yi)一(yi)個(ge)(ge)(ge)單(dan)(dan)位（0.002mm）時，即(ji)(ji)相當于(yu)(yu)洛(luo)(luo)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)變化一(yi)個(ge)(ge)(ge)數e值(zhi)愈(yu)大(da)，金(jin)(jin)屬(shu)的(de)(de)硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)愈(yu)低，反之則硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)愈(yu)高。 上述三個(ge)(ge)(ge)標(biao)尺(chi)適(shi)用(yong)(yong)(yong)范(fan)圍(wei)如(ru)下： HRA（金(jin)(jin)剛石圓錐(zhui)(zhui)壓頭(tou)）20-88 HRC（金(jin)(jin)剛石圓錐(zhui)(zhui)壓頭(tou)）20-70 HRB（直徑(jing)1.588mm鋼球壓頭(tou)）20-100 洛(luo)(luo)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)試(shi)(shi)驗(yan)(yan)(yan)是(shi)(shi)(shi)目前應(ying)用(yong)(yong)(yong)很廣的(de)(de)方(fang)法(fa)(fa)，其(qi)中(zhong)HRC在(zai)12Cr1MoVG合(he)(he)金(jin)(jin)管(guan)標(biao)準中(zhong)使用(yong)(yong)(yong)僅次于(yu)(yu)布(bu)(bu)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)HB。洛(luo)(luo)氏硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)可適(shi)用(yong)(yong)(yong)于(yu)(yu)測(ce)定(ding)(ding)由極軟到極硬(ying)(ying)(ying)(ying)的(de)(de)金(jin)(jin)屬(shu)材料，12Cr1MoVG合(he)(he)金(jin)(jin)管(guan)它彌補(bu)了布(bu)(bu)氏法(fa)(fa)的(de)(de)不是(shi)(shi)(shi)，較布(bu)(bu)氏法(fa)(fa)簡便，可直接從硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)機的(de)(de)表(biao)(biao)盤讀(du)出(chu)硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)值(zhi)。但(dan)是(shi)(shi)(shi)，由于(yu)(yu)其(qi)壓痕小，12Cr1MoVG合(he)(he)金(jin)(jin)異徑(jing)管(guan)故硬(ying)(ying)(ying)(ying)度(du)(du)(du)(du)(du)(du)值(zhi)不如(ru)布(bu)(bu)氏法(fa)(fa)準確。 

  合金管(guan)件(jian)維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)（HV）維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)試(shi)驗(yan)(yan)也是(shi)一種壓痕(hen)試(shi)驗(yan)(yan)方法(fa)(fa)，是(shi)將一個相對面夾角(jiao)(jiao)(jiao)為(wei)1360的(de)(de)(de)正(zheng)四棱錐體(ti)金剛石壓頭以選定(ding)(ding)的(de)(de)(de)試(shi)驗(yan)(yan)力（F）壓入(ru)試(shi)驗(yan)(yan)表(biao)面，經規定(ding)(ding)保持(chi)時間后卸(xie)除試(shi)驗(yan)(yan)力，測(ce)量壓痕(hen)兩對角(jiao)(jiao)(jiao)線(xian)長度(du)(du)(du)。維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)值(zhi)是(shi)試(shi)驗(yan)(yan)力除以壓痕(hen)表(biao)面積所得(de)之商，其(qi)計算公式為(wei) 式中(zhong)：HV--維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)符(fu)號(hao)，N/mm2(MPa)； F--試(shi)驗(yan)(yan)力，N； d--壓痕(hen)兩對角(jiao)(jiao)(jiao)線(xian)的(de)(de)(de)算術平均(jun)值(zhi)，mm。 維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)采(cai)用的(de)(de)(de)試(shi)驗(yan)(yan)力F為(wei)5（49.03）、10（98.07）、20（196.1）、30（294.2）、50（490.3）、100（980.7）Kgf(N)等六(liu)級，可測(ce)硬(ying)(ying)<P>度(du)(du)(du)值(zhi)范圍為(wei)5～1000HV。 表(biao)示方法(fa)(fa)舉(ju)例(li)：640HV30/20表(biao)示用30Hgf（294.2N）試(shi)驗(yan)(yan)力保持(chi)20S（秒）測(ce)定(ding)(ding)的(de)(de)(de)維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)值(zhi)為(wei)640N/mm2(MPa)。 維(wei)(wei)氏(shi)(shi)硬(ying)(ying)度(du)(du)(du)法(fa)(fa)可用于測(ce)定(ding)(ding)很薄(bo)的(de)(de)(de)金屬材料和表(biao)面層硬(ying)(ying)度(du)(du)(du)。它具有布氏(shi)(shi)、洛氏(shi)(shi)法(fa)(fa)的(de)(de)(de)主要優點，而克(ke)服了它們(men)的(de)(de)(de)基(ji)本缺點，但不如洛氏(shi)(shi)法(fa)(fa)簡便。